16 questions · Shuffled order · Progress saved locally when available
Work through the set before checking solutions. Note the evidence for each answer and why the nearest alternative fails. Question numbers follow the shuffled order; Guide question labels match the guide references.
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Choose one answer per item. Work untimed, record confidence, and name the controlling structure or word. Read the explanations after completing the set.
Items
Chapter to revisit
D01-D04
1. Clause and Sentence Boundaries
D05-D08
2. Punctuation Within Sentences
D09-D12
3. Verbs and Subject-Verb Agreement
D13-D16
4. Pronouns, Possessives, and Modifiers
Use results as a starting signal
Four questions per chapter cannot establish mastery. Revisit an area when an answer is wrong, uncertain, or correct for an unsupported reason. An error about a clause boundary needs a different repair from an error about identifying a subject, even if both appear in a long sentence.
Check your reasoning
Check the reason as well as the letter. If you guessed correctly or relied only on how the sentence sounded, treat the item as unfinished. Each explanation identifies why the key works, why the alternatives fail, and how to repair the relevant error. Insert the complete choice into the original text when checking punctuation or word order.
The drill
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Question 1
Guide question D01
Transfer
The initial survey revealed no traces of the settlement aboveground. Hoping to identify structures hidden beneath the soil, the researchers scanned the ______ detected several rectangular foundations that the surface survey had missed.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Separate two independent clauses | Review lesson 1.3
Correct choice: site; they
The researchers scanned the site and they detected several rectangular foundations each contain a subject and a finite verb. A semicolon correctly separates these two related independent clauses. The opening modifier belongs to researchers and does not change the boundary between scanned and detected.
A: A comma alone joins two independent clauses, creating a comma splice. They begins a new subject-verb unit.
C: With no punctuation or conjunction, the two independent clauses run together.
D: Which detected several rectangular foundations is a relative clause, not an independent clause. A semicolon cannot introduce that dependent clause.
If you missed it: Find the subject and finite verb on each side before deciding whether a comma can do the work.
Although the number of visitors to the small museum ______ directors maintained its evening hours because local teachers relied on the building for after-school workshops.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Join an introductory dependent clause to its main clause | Review lesson 1.4
Correct choice: declined, the
Although makes the first clause dependent. The clause beginning the directors maintained is the main clause that completes the sentence. A comma marks the end of the introductory dependent clause; the conjunction and is unnecessary and would prevent this wording from supplying the intended main clause.
A: Although the number of visitors to the small museum declined cannot stand alone as a sentence. The period leaves that dependent clause as a fragment.
B: A semicolon requires an independent clause before it, but the opening although clause is dependent.
C: Although governs the coordinated material: although X declined, and Y maintained. The resulting construction never supplies a main clause outside the although clause.
If you missed it: Circle a subordinating word such as although, because, or while; then locate the independent clause that completes it.
The engineer wanted the prototype to withstand rapid temperature changes. After conducting a series of tests, she compared several insulating ______ the one that retained its shape under the most demanding conditions.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Keep a compound predicate together | Review lesson 1.2
Correct choice: materials and selected
She is the shared subject of compared and selected. The conjunction and joins these two verbs into a compound predicate, so no sentence boundary is needed between them. The second verb does not need a repeated subject.
B: And selected the one that retained its shape has no subject of its own and cannot stand after a semicolon.
C: Selecting the one that retained its shape is a participial phrase. The period detaches it from the preceding sentence and creates a fragment.
D: She compared several insulating materials and she selected the one each form an independent clause. A comma alone cannot separate them.
If you missed it: When and links actions, check whether the actions share a subject before inserting a sentence boundary.
The research team reconstructed the harbor from surviving maps and shipping ______ the records did not indicate the exact position of the oldest pier, so that feature remained uncertain.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Punctuate a conjunctive adverb between independent clauses | Review lesson 1.5
Correct choice: records; however,
The research team reconstructed the harbor is one independent clause; the records did not indicate the exact position is another. However is a conjunctive adverb, not a coordinating conjunction. The semicolon establishes the clause boundary, and the comma sets off however at the beginning of the second clause.
A: The comma before however cannot by itself join the independent clauses. However does not repair this comma splice.
B: No valid boundary separates the independent clauses. However is not a substitute for punctuation or a coordinating conjunction.
D: A semicolon after however treats the single adverb as though it were a complete clause. The adverb should be followed by a comma here.
If you missed it: Treat however as a movable adverb; establish the boundary between complete clauses separately.
The archive contains two versions of the same script. Only one contains the director's handwritten notes. The version ______ will be displayed beside photographs from the production, allowing visitors to compare the director's plans with the finished scenes.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Avoid a comma between the complete subject and its verb | Review lesson 2.2
Correct choice: that includes handwritten notes
That includes handwritten notes identifies which version will be displayed. It belongs inside the complete subject, the version that includes handwritten notes. No comma should separate that subject from will be displayed, and no comma is needed within the identifying clause.
B: The comma comes between the complete subject and its verb will be displayed. There is no inserted supplement to justify it.
C: That is the subject of includes in the relative clause. The comma separates that subject from its verb.
D: Includes takes handwritten notes as its direct object. A comma cannot divide this verb-object unit.
If you missed it: Read the main subject and main verb as one connection, even when an identifying clause expands the subject.
The observatory recently upgraded its oldest telescope. The telescope, which now uses a more sensitive set of ______ produced clearer images of the faint objects that the original equipment could barely detect.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Close a nonessential relative clause | Review lesson 2.2
Correct choice: sensors, has
The nonessential clause begins with the comma before which and ends after sensors. A second comma closes it. The main clause is The telescope has produced clearer images. Removing the inserted clause makes the need to reconnect telescope with has produced easy to see.
A: The comma before which opens a nonessential clause, but no comma closes that clause before the main verb has produced.
B: The semicolon leaves The telescope without its main verb on the left and has produced without a subject on the right. It also fails to close the comma-delimited insertion.
D: A colon cannot separate the subject telescope from its main verb has produced. It does not close the nonessential clause properly.
If you missed it: Bracket the entire which clause, then confirm that matching commas leave a complete main clause.
The curator wanted visitors to see how different surfaces affected handwriting. The final selection featured ______ bamboo, with a short description explaining how scribes prepared each surface before writing on it.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Introduce an explanatory list after a complete clause | Review lesson 2.6
Correct choice: three writing materials: paper, parchment, and
The final selection featured three writing materials is a complete clause. The list after the colon identifies those materials: paper, parchment, and bamboo. The explanatory list can be a phrase; it does not need its own subject and finite verb.
A: Paper, parchment, and bamboo is a list, not an independent clause, so a semicolon cannot introduce it.
B: The period turns the list and its attached description into a sentence fragment. The list has no finite main verb.
C: The colon interrupts such as and the examples that complete it. After such as, the items should follow directly; the earlier complete clause does not license a colon at this later position.
If you missed it: Inspect the exact words immediately before a colon, not merely whether a complete clause occurs somewhere earlier.
To investigate changes in regional pronunciation, a linguist compared recordings made several decades apart. An analysis of the speakers' vowel sounds in those ______ a gradual shift that is difficult to notice in any single conversation.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Do not punctuate the subject-verb boundary | Review lesson 2.1
Correct choice: recordings reveals
The head of the subject is analysis; of the speakers' vowel sounds in those recordings expands that subject. Reveals is its main verb. None of the material between analysis and reveals is a separately introduced supplement, so no punctuation belongs at the boundary.
A: The comma separates the subject An analysis ... from reveals. A long subject does not require a comma after it.
C: The material before the semicolon lacks its main verb, and reveals has no independent subject after it. Neither side supplies the required independent clause.
D: The material before the colon is only a subject phrase, not a complete clause. The colon also divides that subject from its verb.
If you missed it: Temporarily set aside prepositional phrases to expose the core: analysis reveals.
Access to the mountain site varies with the season. The placement of sensors along three narrow ridges ______ determined by how easily each ridge can be reached on foot, even when the weather is clear.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Match the verb to a singular head noun | Review lesson 3.2
Correct choice: is
Placement is the singular head of the subject. Sensors and ridges occur within prepositional phrases and do not control the main verb. Is determined supplies a complete present-tense passive verb phrase agreeing with placement.
A: Are is plural, but the main subject is the singular noun placement. Sensors and ridges are not the head of that subject.
B: Were is plural here and does not agree with placement. The sentence is an ordinary statement, not a hypothetical were construction.
C: Being determined is nonfinite by itself. No other main verb completes the clause beginning The placement.
If you missed it: Underline the head noun before checking the nearby nouns or the final word of the subject phrase.
The excavation report describes a sequence of flood deposits. Beneath the layer of fine gray clay ______ two bands of coarse sand, each containing fragments of shells carried inland by unusually strong currents.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Recognize the subject after an inverted verb | Review lesson 3.3
Correct choice: lie
The sentence begins with a location phrase and places its subject after the verb. The subject is two bands of coarse sand, which is plural. Reordering the core as two bands lie beneath the layer shows why lie is correct.
A: Lies is singular and does not agree with two bands. Layer is inside the introductory location phrase, so it does not control the verb.
C: Lying is a nonfinite form without an auxiliary. The clause would have no finite main verb.
D: Has lain is singular because of has. A perfect-tense form with this plural subject would need have, not has.
If you missed it: For an opening location phrase, try moving the noun after the verb to the front: two bands lie.
The letters that the historian discovered in a sealed cabinet ______ how the composer revised the final movement. Several pages contain alternate melodies alongside brief comments about the effect each melody was intended to create.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Supply a finite main verb outside an embedded clause | Review lesson 3.1
Correct choice: reveal
The main subject is letters, and its main verb must occur outside the identifying clause that the historian discovered in a sealed cabinet. Reveal is a finite present-tense verb agreeing with letters. Discovered already serves the embedded clause; it cannot also complete the main clause.
A: Revealing is a participle without an auxiliary. The main clause The letters ... would lack a finite verb.
B: To reveal is an infinitive, so it does not supply the main clause with a finite verb.
D: Having revealed is a participial phrase, not a finite verb phrase. The finite verb discovered belongs only to the relative clause.
If you missed it: Count clauses, then match each required finite verb to the subject of its own clause.
When the collection reached the regional archive, the donor had already ______ a detailed inventory of its contents. That list helped archivists identify several objects whose labels had become detached during transportation.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Use a past participle after had | Review lesson 3.8
Correct choice: written
The auxiliary had forms the past perfect with a past participle. The participle of write is written: had already written. The past reference point is the collection's arrival; already indicates that the inventory existed before that arrival.
B: Wrote is the simple past form. It cannot follow had in the perfect construction; had wrote is not standard.
C: Writing is the -ing form. Had writing is not a complete standard auxiliary chain; a progressive perfect would need had been writing.
D: Write is the base form. Had requires the past participle written in this construction.
If you missed it: Inspect the auxiliary before the blank: had + past participle. Do not choose the simple past form merely because the context concerns the past.
The two timing devices operate independently, even though they are mounted in the same case. To prevent a failure in one device from affecting the other, ______ separate power supplies and transmit their measurements through different channels.
Which choice completes the text so that it conforms to the conventions of Standard English?
The antecedent is the two timing devices, a plural noun phrase. They use preserves that plural reference and supplies a finite verb. The following their measurements also refers to those same two devices.
A: It is singular and does not fit the two devices being described. It also produces the mismatched verb sequence it uses ... and transmit: a singular subject would require transmits.
B: Its use makes use a noun after a possessive determiner. This wording does not supply the main clause with the required subject and finite verb.
D: It has the wrong number for the two devices, and use also fails to agree with the singular pronoun it.
If you missed it: Name the antecedent in full before selecting its pronoun; do not default to the nearest singular noun.
The photographer visited three painters, each of whom worked in a separate building. A later exhibition displayed images of the three ______, showing how the rooms' dimensions shaped the painters' work.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Distinguish a plural possessive from a singular possessive | Review lesson 4.3
Correct choice: painters' studios
There are three painters, and the studios belong to those painters. The plural noun painters takes an apostrophe after its final s: painters'. Studios names the rooms being shown and needs an ordinary plural ending without an apostrophe.
B: Painter's marks one painter as the owner. The passage identifies three separate painters whose studios appear in the exhibition, so the possessive owner must be plural.
C: Painters is a plain plural, so it does not mark the intended possessive relationship between the painters and their individual studios.
D: Studios' is itself possessive, but there is no following noun or supplied context for an omitted possessed noun. The exhibition shows the studios, so studios should be an ordinary plural.
If you missed it: Decide separately how many owners there are and whether the following noun is itself an owner.
The new algorithm monitors a signal that can change rapidly. To avoid missing brief changes, it automatically adjusts ______ sampling interval whenever the signal becomes less predictable, allowing the system to record more frequent measurements.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Distinguish its from it is and plural forms | Review lesson 4.5
Correct choice: its
The sentence needs a possessive determiner before sampling interval. Its refers to the singular algorithm and shows that the interval belongs to that algorithm's sampling process. No apostrophe is used in this possessive pronoun.
A: It's expands to it is or it has. Neither it is sampling interval nor it has sampling interval can serve as the object after adjusts.
C: Their has no suitable antecedent here. The single algorithm is referred to as it and takes the possessive its; singular their for a person does not apply to this algorithm.
D: They're expands to they are. That subject-verb combination cannot modify the noun phrase sampling interval after adjusts.
If you missed it: Expand every contraction first, then check whether the blank needs a possessive word or a subject-verb unit.
The manuscript's pages had become brittle after decades in a damp storeroom. Wearing thin cotton gloves, ______ to assess the damage without touching the fragile ink.
Which choice completes the text so that it conforms to the conventions of Standard English?
Why this answer
Attach an introductory modifier to its logical subject | Review lesson 4.6
Correct choice: two conservators examined the pages
The introductory participial phrase describes whoever was wearing the gloves. Two conservators is the subject immediately following that phrase and names those people. The rest of the sentence supplies their action: examined the pages to assess the damage.
A: The grammatical subject is the damage, which cannot wear gloves. Naming the conservators later in a by phrase does not repair the opening modifier.
B: An examination is the grammatical subject, but an examination cannot wear gloves. The people conducting it must be the subject after this modifier.
C: The subject is examination, not conservators. Conservators' is only a possessive modifier inside that noun phrase, so the opening phrase still dangles.
If you missed it: Ask who performs the action in the opening modifier, then require the following main-clause subject to name that actor.