9 original Boundaries questions, easiest first. Where sentences end, and which punctuation may join what. Answer them all, then submit once to see every answer explained.
Although the initial trial produced mixed results the researchers cautioned that further testing would be needed before ruling out the treatment entirely.
Which choice fixes the punctuation error?
B — results, the researchers. 'Although the initial trial produced mixed results' is a dependent introductory clause that requires a comma before the main clause begins. Choice B correctly adds this comma.
The theater's balcony section, closed for structural inspection will reopen to ticket holders next month.
Which choice fixes the punctuation error?
A — inspection, will. 'Closed for structural inspection' is a nonrestrictive phrase interrupting the sentence and needs a comma on both sides. The comma after 'section,' is already present, so a matching comma is needed after 'inspection' before 'will.' Choice A supplies this.
Volunteers spent the weekend clearing debris planting new trees, and repairing the trail's wooden footbridges.
Which choice fixes the punctuation error?
A — debris, planting. This sentence contains a list of three parallel verb phrases ('clearing debris,' 'planting new trees,' 'repairing... footbridges') that must be separated by commas throughout. Choice A adds the missing comma after 'debris' to match the comma already present after 'trees.'
Marie Tharp created remarkably detailed maps of the ocean floor ______ her work later provided key evidence for the theory of plate tectonics.
Which choice completes the text so that it conforms to the conventions of Standard English?
B — floor; her. Both parts are independent clauses, so they need a semicolon (or period) between them. 'floor, her' is a comma splice; 'floor her' is a run-on; 'and, her' misplaces the comma. Only B is correct.
The report concluded, that the bridge's support cables showed early signs of corrosion requiring immediate inspection.
Which choice fixes the punctuation error?
A — concluded that. The word 'that' introduces a restrictive noun clause functioning as the direct object of 'concluded' and should not be separated from the verb by a comma. Choice A correctly removes the unnecessary comma.
The audit revealed, that several departments had exceeded their allocated budgets for the fiscal year.
Which choice fixes the punctuation error?
D — revealed that. The word 'that' introduces a restrictive noun clause functioning as the direct object of 'revealed' and should not be separated from the verb by a comma. Choice D correctly removes the unnecessary comma.
The inspection found, that the building's electrical wiring did not meet current safety codes.
Which choice fixes the punctuation error?
B — found that. The word 'that' introduces a restrictive noun clause functioning as the direct object of 'found' and should not be separated from the verb by a comma. Choice B correctly removes the unnecessary comma.
The inquiry determined, that the bridge's inspection records had not been updated in over a decade.
Which choice fixes the punctuation error?
D — determined that. The word 'that' introduces a restrictive noun clause functioning as the direct object of 'determined' and should not be separated from the verb by a comma. Choice D correctly removes the unnecessary comma.
The review concluded, that the building's fire alarm system needed to be fully replaced.
Which choice fixes the punctuation error?
C — concluded that. The word 'that' introduces a restrictive noun clause functioning as the direct object of 'concluded' and should not be separated from the verb by a comma. Choice C correctly removes the unnecessary comma.
Score:
Every question above is now marked up: the correct answer is highlighted, any wrong option you picked is flagged, and each explanation is open.
No. Every question here is original, written to the College Board's published Digital SAT Reading & Writing specification for the Boundaries skill. No retired or copyrighted College Board material appears anywhere on this site.
Boundaries tests sentence boundaries and the punctuation that marks them: periods, semicolons, colons, commas, and dashes, including comma splices, run-ons and the punctuation around supplementary elements. Every question is answerable from the sentence in front of you, without knowing anything about the subject matter.
Ignore how the sentence sounds and test the structure instead. Decide whether the material on each side of the punctuation is an independent clause — a subject and a verb that could stand alone. Two independent clauses need a period, a semicolon, or a comma plus a coordinating conjunction; a colon needs an independent clause on its left; a supplementary phrase needs the same mark on both sides, and never a comma on one side and a dash on the other.
No, and deliberately so. This drill is 9 Boundaries questions back to back; a real Reading & Writing module is 27 questions in 32 minutes drawn from all eleven skills. Use a drill to fix one weakness, then take a full module to practice the real thing.
No. The SAT has no penalty for a wrong answer — a blank and a wrong guess both score zero — so answer every question, including the ones you have to guess.