Verb Patterns with Verbs of Perception in Technical English
5 exercises — practise bare infinitive vs -ing after see/watch/hear/notice.
0 / 9 completed
1 / 9
Which sentence correctly uses the bare infinitive after a perception verb to describe a complete event that was observed from start to finish?
"...watched the deployment fail..." is correct: after perception verbs like "watch", the bare infinitive ("fail", without "to") is used when the observer perceived the entire event, from beginning to end, as described here by "from a config error to a full outage". Option B uses the -ing form, which would suggest witnessing only part of an ongoing process rather than its full course, which conflicts with the complete-event framing of the sentence. Option C incorrectly adds "to" before "fail", which is not permitted in this perception-verb pattern. Option D wrongly uses the finite present-tense form "fails" instead of the required bare infinitive.
2 / 9
Which sentence correctly uses the -ing form after a perception verb to describe an action observed in progress, without implying it was seen to completion?
"...noticed the CPU usage spiking..." is correct: the -ing form after a perception verb emphasizes catching an action mid-progress, without necessarily seeing its beginning or end, which fits "while I was reviewing the logs" — a background, ongoing context. Option A uses the bare infinitive "spike", which would suggest observing the complete spike event, but the sentence's framing suggests an incidental, in-progress observation instead. Option B incorrectly adds "to" before "spike", which perception verbs don't take. Option D uses the finite form "spikes", which isn't grammatical as a complement after "noticed" in this pattern.
3 / 9
Which sentence correctly uses "hear" + object + bare infinitive to describe a complete, momentary sound event?
"...heard the fan spin down completely..." is correct: the bare infinitive is appropriate here because the sentence describes hearing the entire process play out, reinforced by "completely", which signals a full, bounded event. Option B's -ing form would suggest catching only part of the winding-down sound rather than the whole completed process implied by "completely". Option C incorrectly adds "to" before the bare infinitive, which perception verbs never take. Option D wrongly uses the past participle "spun", which is not a valid complement form after "heard + object" in this active perception pattern.
4 / 9
Which sentence correctly contrasts the bare infinitive and -ing forms after "see" within the same sentence to mark two different types of observation?
"...saw the build finish successfully...seen it failing repeatedly for a week" is correct: the bare infinitive "finish" fits the single, complete successful run being reported as one bounded event, while the -ing form "failing" correctly conveys a repeated, ongoing pattern of failures observed over an extended period ("for a week"). Option B reverses this logic, using -ing for the single complete event and the bare infinitive for the repeated pattern, which doesn't match the intended meanings. Options C and D both incorrectly insert "to" before a perception-verb complement, which is never grammatical in this pattern.
5 / 9
Which sentence correctly uses "see" + object + bare infinitive in the passive voice, where "to" IS required?
"The service was seen to crash multiple times..." is correct: unlike the active voice pattern, when a perception verb like "see" is used in the passive voice, the following verb must take the to-infinitive ("to crash"), not the bare infinitive. Option A incorrectly keeps the active-voice bare infinitive pattern ("seen crash") in a passive sentence, which is ungrammatical. Option C garbles the sentence by using "saw" without the passive auxiliary "was" and without a logical subject performing the seeing. Option D incorrectly uses the active continuous form "was seeing", which changes the meaning and doesn't fit with a bare or to-infinitive complement here.
6 / 9
Sarah commented in a code review: 'I'm seeing lots of logging statements in this function.' What does Sarah most likely mean?
When using perception verbs like 'see' in this context, the -ing form indicates ongoing observation. Sarah isn't simply *seeing* the logging statements as a visual thing; she's actively observing their output during the function's execution. Options 1 and 3 misinterpret the meaning of 'see' with an -ing form, while option 4 introduces a different concern (logging levels) that isn't directly addressed by her comment.
7 / 9
Sarah commented in a code review: 'I'm seeing lots of logging statements in this function.' What does Sarah most likely mean?
When using perception verbs like 'see' in this context, the -ing form indicates ongoing observation. Sarah isn't simply *seeing* the logging statements as a visual thing; she's actively observing their output during the function's execution. Options 1 and 3 misinterpret the meaning of 'see' with an -ing form, while option 4 introduces a different concern (logging levels) that isn't directly addressed by her comment.
8 / 9
John noticed a strange error message during the deployment process. He described it as 'I've been observing' an unexpected spike in network latency.
The core of this question tests understanding of when to use the -ing form after perception verbs. Here, 'observing' indicates that John was witnessing the latency spike *while* it was happening, rather than describing a completed event he observed from start to finish. The correct answer reflects the typical usage in this scenario.
9 / 9
A developer sends an API response: `{"status": "error", "message": "Invalid user ID"}`. What does the developer likely mean when they state they 'detected' this error?
The developer uses 'detected' as a perception verb to describe the act of identifying the error within the response. This highlights a focused observation and understanding of the specific problem indicated by the API data. Option A is incorrect because the developer *has* identified an error. Options C and D misinterpret the meaning – 'detected' implies recognizing the error conveyed in the response.
What will I practise in "Verb Patterns with Verbs of Perception — IT Grammar Exercise"?
Practise see/watch/hear/notice + object + bare infinitive versus + object + -ing, and the passive to-infinitive pattern, when describing observed system
How many exercises are in this module?
This module has 9 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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Every exercise is written by the CoderSlingo team, drawing on real workplace English used in IT roles, then reviewed for accuracy and clarity.