TOEFL Grammar & Sentence Structure 2 — Questions and Answers

Question 1: Which sentence demonstrates correct subject-verb agreement?

The number of applicants have increased significantly.
A number of applicants has submitted their forms.
The number of applicants has increased significantly. (Correct answer)
A number of applicants have submitted his form.

Correct answer: The number of applicants has increased significantly.

'The number of applicants has increased' is correct because 'the number' is a singular subject and takes the singular verb 'has.'

The 'number' distinction is a classic subject-verb agreement trap tested on the TOEFL. 'The number of X' treats 'number' as the singular head noun → singular verb: 'The number of students is rising.' By contrast, 'a number of X' means 'many X' and takes a plural verb: 'A number of students are waiting.' This pattern applies to similar expressions: 'The total of errors is three' vs. 'A total of three errors were found.' Subject-verb agreement errors most commonly occur when: (1) a prepositional phrase separates the subject from the verb ('The list of requirements are/is long'), (2) the subject is a collective noun ('The committee has/have decided'), or (3) indefinite pronouns are used ('Everyone needs/need to register'). In academic register, collective nouns in American English typically take singular verbs. Reviewing and drilling these patterns will help both your Writing score (avoiding errors) and your Grammar question accuracy in Reading.

Question 2: Which sentence uses the correct conditional form to express a hypothetical present or future situation?

If she will study harder, she passes the exam.
If she studied harder, she would pass the exam. (Correct answer)
If she had studied harder, she will have passed the exam.
If she studies harder, she would pass the exam.

Correct answer: If she studied harder, she would pass the exam.

The Second Conditional uses 'if + past simple' in the if-clause and 'would + base verb' in the main clause to describe hypothetical present or future situations.

English conditional sentences follow predictable patterns that are tested extensively on the TOEFL. The Second Conditional — 'If + past simple, would + base verb' — expresses a hypothetical or unlikely situation in the present or future: 'If I had more time, I would study abroad.' This implies the speaker does NOT currently have more time. Contrast this with the First Conditional — 'If + present simple, will + base verb' — which describes a realistic, possible future condition: 'If she studies harder, she will pass the exam.' The Third Conditional — 'If + past perfect, would have + past participle' — expresses a hypothetical situation in the past (the situation did not happen): 'If she had studied harder, she would have passed.' Mixing conditional forms (as in options A, C, and D) is a common grammar error in TOEFL Writing responses. Memorizing the three conditional structures with example sentences is an efficient way to eliminate these errors.

Question 3: In the sentence 'The data collected by the team were inconclusive,' what grammatical role does 'collected by the team' play?

Main verb phrase
Adverbial clause
Participial phrase modifying 'data' (Correct answer)
Independent clause

Correct answer: Participial phrase modifying 'data'

'Collected by the team' is a participial phrase (past participle + agent) that modifies the noun 'data.'

Participial phrases are condensed relative clauses built from participles (present: -ing; past: -ed/irregular). 'Collected by the team' comes from 'which was collected by the team' — a relative clause reduced to a participial phrase by removing the relative pronoun and auxiliary verb. These phrases are extremely common in academic prose because they allow writers to pack more information into fewer words. Understanding participial phrases helps TOEFL test-takers with sentence simplification questions in Reading (recognizing what information is essential vs. modifying) and with Grammar questions that ask about sentence structure. A key rule: a participial phrase must be placed directly next to the noun it modifies to avoid a dangling modifier. 'Collected by the team, the results surprised everyone' is correct ('results' is the subject and the thing collected). 'Collected by the team, the surprise was significant' is a dangling modifier (the surprise was not collected).

Question 4: Which sentence correctly uses a relative clause?

The professor which teaches biology is retiring.
The professor who teaches biology is retiring. (Correct answer)
The professor whom teaches biology is retiring.
The professor that he teaches biology is retiring.

Correct answer: The professor who teaches biology is retiring.

'Who' is the correct relative pronoun when referring to a person and the pronoun is the subject of the relative clause ('who teaches biology').

Selecting the correct relative pronoun is a recurring grammar point in TOEFL. For people: use 'who' when the pronoun is the subject of the relative clause ('the professor who teaches') and 'whom' when it is the object ('the professor whom I admire'). 'Which' refers to things and animals (not people). 'That' can refer to people or things informally, but in formal academic writing, 'who' for people and 'which' for things is preferred. Option A uses 'which' incorrectly for a person. Option C uses 'whom' incorrectly — 'whom' would be correct if the professor is the object: 'The professor whom the department hired' (the department hired him → him = object). Option D has an extra pronoun 'he' that creates a grammatically redundant structure. Relative clauses are productive in academic writing because they allow noun modification with precision. Practicing relative clause reduction (to participial phrases) is also valuable: 'the professor who teaches biology' → 'the biology-teaching professor' or 'the professor teaching biology.'

Question 5: Which sentence is an example of a correctly punctuated compound sentence?

The exam was difficult, she still passed.
The exam was difficult however she still passed.
The exam was difficult, but she still passed. (Correct answer)
The exam was difficult. But she still passed.

Correct answer: The exam was difficult, but she still passed.

A compound sentence correctly uses a comma + coordinating conjunction (FANBOYS) to join two independent clauses: 'The exam was difficult, but she still passed.'

A comma splice (Option A) occurs when two independent clauses are joined with only a comma and no coordinating conjunction — one of the most common punctuation errors. The FANBOYS coordinating conjunctions (For, And, Nor, But, Or, Yet, So) join independent clauses with a preceding comma: 'She studied hard, so she passed.' Option B uses 'however' as if it were a coordinating conjunction, but 'however' is a conjunctive adverb — it must be preceded by a semicolon or a new sentence: 'The exam was difficult; however, she still passed.' Option D (starting a sentence with 'But') is grammatically correct but stylistically informal for academic writing — though TOEFL scorers do not penalize it heavily. The safest academic choice is Option C. Building awareness of sentence types — simple, compound, complex, compound-complex — and their punctuation rules will directly improve your TOEFL Writing Language Use score.

Question 6: In academic English, which sentence demonstrates the most appropriate register?

This study is gonna show that pollution is a big problem.
This study demonstrates that industrial pollution significantly impacts urban air quality. (Correct answer)
This study shows that pollution is, like, really bad for cities.
We're going to prove pollution messes up city air.

Correct answer: This study demonstrates that industrial pollution significantly impacts urban air quality.

'This study demonstrates that industrial pollution significantly impacts urban air quality' uses formal vocabulary, specific language, and avoids contractions and slang — hallmarks of academic register.

Academic register is a formal style of language characterized by: precise and specific vocabulary ('demonstrates' instead of 'shows'; 'significantly impacts' instead of 'is really bad for'), avoidance of contractions ('we are' not 'we're'), absence of slang or colloquial expressions ('gonna,' 'like,' 'messes up'), complex sentence structures, and hedging language where appropriate. TOEFL Writing is assessed partly on 'Language Use,' which includes vocabulary range and appropriateness. Using formal synonyms strategically — not just sprinkling in advanced words for their own sake — is the goal. Changing 'big problem' to 'significant challenge,' 'shows' to 'demonstrates' or 'indicates,' and 'bad for' to 'detrimental to' or 'adversely affecting' are the kinds of upgrades that move a response from a 3 to a 4 on the Writing rubric. A practical preparation habit is to build a personal vocabulary list with formal academic synonyms for commonly used words.

TOEFL Grammar & Sentence Structure 2

Which sentence demonstrates correct subject-verb agreement?