observation verbs followed by ing form or bare infinitive

[allthewayanime]

I've got a big doubt regarding this topic.I know that a verb expressing observation or perception can be only followed by a noun and a participial phrase (-ing)

But I've come across that (quoted from an English grammar book)'A verb expressing observation/ perception can be also followed by a noun and a base verb form. The suffix -ing is deleted from the verb. There is no difference in meaning.'

Here are some examples:
1.We felt the temperature rising. - We felt it rise.


2.We observed the doctor doing open-heart surgery. - (no base-form equivalent)



I don't quite get it.Why the first sentence could work with a bare infinitive and second no?Is the bare infinitive actually possible with an observation/perception verb?Could someone enlighten me on this matter,please?

[5jj]

The second is far more likely with the -ing form, because, if you are the position of being able to observe this, you are lkely to be observing everything done during this long process. if you observe the surgeon do open-heart surgery, it suggests that you have watched them carry out a complete, short operation. You could say "We observed the detist extract/extracting the tooth".

[Raymott]

I've got a big doubt regarding this topic.I know that a verb expressing observation or perception can be only followed by a noun and a participial phrase (-ing)

But I've come across that (quoted from an English grammar book)'A verb expressing observation/ perception can be also followed by a noun and a base verb form. The suffix -ing is deleted from the verb. There is no difference in meaning.'

Here are some examples:
1.We felt the temperature rising. - We felt it rise.


2.We observed the doctor doing open-heart surgery. - (no base-form equivalent)



I don't quite get it.Why the first sentence could work with a bare infinitive and second no?Is the bare infinitive actually possible with an observation/perception verb?Could someone enlighten me on this matter,please?

Well, you can. You can say, "We watched him operate."
But we wouldn't normally say, "We observed him operate". We'd use 'operating'.
Also, "We watched the actor acting. We watched him acting. We watched him act." But not "We observed him act."
"I heard her sing" Good. "I perceived her sing." Bad.

So there's no rule about observation/perception verbs and bare infinitives that I can see. It depends entirely on the verb. So you'd have to make a list of verbs which you can follow with a bare infinitive,and those which you can't (and both 'observe' and 'perceive' are of the latter group - as a generalisation).
An exception: Policeman: "Did you actually observe him light/lighting the fire?" There would also be stylistic issues.
It sounds like a bad rule, unless I've missed something.

[5jj]

If your information is from the same grammar book you have mentioned in other threads, I suggest that you use a different one.