Gerunds after prepositions
Understanding the TOEFL Grammar Item: Gerunds After Prepositions
The given sentence is:
“They are looking forward to _____ the museum.”
Answer choices:
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visit
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visiting
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visits
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be visiting
To determine the correct answer, we need to analyze the grammatical structure of the phrase “looking forward to”, recognize the correct verb form that follows it, and address common misunderstandings.
1. Identifying the Grammar Rule: Gerunds After Prepositions
The key phrase in this sentence is “looking forward to.” This is a common phrasal expression in English, meaning “to be excited about something that will happen in the future.”
The crucial grammar rule here is that whenever a preposition (such as “to”) is followed by a verb, that verb must be in its gerund (-ing) form.
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Correct structure:
looking forward to + gerund (verb + -ing)
looking forward to visiting
Thus, the correct answer is:
✅ (B) visiting.
2. Explanation of Why Other Choices Are Incorrect
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(A) visit ❌
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The word “visit” is the base form (infinitive without “to”), which is incorrect after a preposition like “to.”
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Learners often mistakenly assume “to” here means an infinitive (to visit), but “to” is actually a preposition, not part of an infinitive phrase.
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❌ They are looking forward to visit the museum. (incorrect)
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✅ They are looking forward to visiting the museum. (correct)
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(C) visits ❌
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“Visits” is the plural noun form of “visit,” but the sentence needs a verb, not a noun.
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❌ They are looking forward to visits the museum. (incorrect)
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✅ They are looking forward to visiting the museum. (correct)
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(D) be visiting ❌
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“Be visiting” is in the progressive infinitive form, which does not follow the structure required after “looking forward to.”
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It does not fit the standard pattern of “preposition + gerund.”
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❌ They are looking forward to be visiting the museum. (incorrect)
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✅ They are looking forward to visiting the museum. (correct)
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3. Common Misunderstandings and Errors
Many English learners struggle with this type of sentence because of confusion regarding “to” and its function. Let’s look at some common misunderstandings.
A. Mistaking “to” as Part of an Infinitive
One of the most frequent mistakes is assuming “to” in “looking forward to” functions the same way as in an infinitive (to + verb). However, “to” here is a preposition, not part of an infinitive.
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❌ They are looking forward to visit the museum. (incorrect)
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✅ They are looking forward to visiting the museum. (correct)
B. Using the Base Form Instead of the Gerund
Some learners think “visit” should follow “to” in its base form. However, because “to” functions as a preposition, it must be followed by a noun or a gerund (verb + -ing).
C. Confusing “Look Forward To” with Other Expressions
Another source of confusion is comparing “looking forward to” with similar expressions that do take the infinitive, such as:
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“want to” → I want to visit the museum. (infinitive)
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“plan to” → They plan to visit the museum. (infinitive)
Because these structures use “to + verb”, learners sometimes mistakenly apply the same rule to “looking forward to.” However, “looking forward to” always requires a gerund.
4. Summary and Final Takeaway
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Rule: After “looking forward to”, always use a gerund (-ing form) because “to” is a preposition.
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Correct Answer: visiting (Answer B).
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Common Mistakes:
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Using the base verb (visit) instead of the gerund (visiting).
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Misinterpreting “to” as part of an infinitive instead of recognizing it as a preposition.
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Using an incorrect form, such as a noun (visits) or progressive infinitive (be visiting).
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To master this structure, students should practice similar expressions that also require gerunds after prepositions, such as:
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be used to + gerund → I am used to waking up early.
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be committed to + gerund → She is committed to improving her English.
By remembering that “looking forward to” always requires a gerund, English learners can avoid this common mistake and improve their TOEFL grammar skills.