Question 1

When should I use the gerund with sense verbs?

Accepted Answer

Use the gerund when you want to emphasise that you witnessed an action in progress, not necessarily complete. "I saw her crying" suggests I observed her during the action — I may not have seen when she started or stopped. "I heard music playing" means the music was ongoing while I listened. The gerund creates a more descriptive, ongoing picture. Use it when the duration or ongoing nature of the action matters. In contrast, use the bare infinitive when the complete action matters: "I saw her fall" (the whole event) sounds more dramatic and complete than "I saw her falling" (an observation of the process).

Question 2

Is there always a meaning difference, or are they sometimes the same?

Accepted Answer

Sometimes the difference is very small, and both forms work equally well. "I watched him cook dinner" and "I watched him cooking dinner" are very similar — both describe observing the activity. The infinitive slightly emphasises completion; the gerund slightly emphasises the process. For short actions, the infinitive is often preferred: "I saw the cat jump" rather than "I saw the cat jumping." For longer actions, the gerund can feel more natural: "I watched the children playing in the park." In exams, questions usually test clear-cut cases where only one form is logical.

Question 3

Do sense verbs use bare infinitives in passive sentences?

Accepted Answer

No — in passive sentences with sense verbs, you must use "to" + infinitive: "She was seen to enter the building" (not "was seen enter"). This is similar to how "make" changes in passive sentences. The active "I saw her enter" becomes the passive "She was seen to enter." However, passive sense verb constructions are quite formal and not very common in everyday English. You are more likely to hear "Someone saw her enter" (active) than "She was seen to enter" (passive). Cambridge exams occasionally test this passive pattern, so it is worth knowing.

Gerunds and Infinitives: Sense Verbs (See, Hear, Watch, Feel)

Quick Rule

Continue Practising

Gerunds and Infinitives Error Correction

Common Gerund and Infinitive Verbs

Preposition + Gerund

-ed vs -ing Adjectives

Conditionals

Present Perfect