Passive voice

Hi sana kiran,

Since the person who started this thread is anonomous, let me welcome you to the Forums.  Thanks for joining us.

I think Anon was sort of hoping we'd all say the sentence you wrote is incorrect.  So far, only you and I have come out in support of the usage.

(Sometimes I think "improper usage" is one of those terms like "inappropriate behavior.")

Best wishes,  - A.

All sorts of things are grammatically possible but highly un-natural.

The orignal question said that teachers said the version wtih "He was seen stealing the car" as incorrect. Not only do I disgree witht that, but I I find it highly preferable to the other. The object of the non-passive version wass not "him" but "the act of his stealing the car."

As for the he "Don't let him do it" and "He is not to be let to do it," there is universal agreement among every answer you have received -- on the other forum, here, and in chat -- that you need to change it to "He is not to be allowed."

Can we put this one to bed now?

Unfortunately, there are plenty of grammar books and exercises that are not terribly well-written.  Such books often ask learners to create passive sentences that would rarely (if ever) be used by native speakers.  Although the passive sentences may be technically grammatically correct, too often they are completely unnatural and/or awkward.  They sound contrived, forced and just plain strange.

1/ People saw him steal your car
=> should it be "he was seen to steal your car"
or:
he was seen stealing your car

I'm guessing that your grammar book considers the "correct" response to be "He was seen to steal your car."

Personally, I think this is an example of a badly written exercise.  To me, one of the problems is that the active sentence does not use the 'to infinitive'.  Instead, it uses a bare infinitive.  So, if we have to change a bare infinitive to a 'to infinitive' in order to make a passive sentence, why wouldn't a change to the -ing form be just as acceptable?  Both versions involve changing the form of the verb.

"He was seen to steal your car" sounds unnatural to me. As the others have said, "He was seen stealing your car" sounds natural.  Possibly "he was seen to steal" might sound more natural in British English.  I really don't know.  Maybe a Brit will chime in.  I found a few examples of "was seen to" on the BNC.  Here are a couple of them (along with my comments):

1. Management budgeting was seen to be a failure.
If I attempt to change that to an active sentence, here is what my native speaker instinct tells me is the most natural active version:
They saw management budgeting as a failure. 

However, the word 'see' has a figurative meaning in that sentence.  If I use 'think' rather than 'see', I come up with this:

Active:  They thought management budgeting to be a failure.
Passive: Management budgeting was thought to be a failure. 

Notice that both sentences above use the 'to infinitive'. And both of those sentences sound OK to me.

2. The system was seen to benefit the Soviet Union, whose oil and gas exports to Eastern Europe would attain high market prices.
This was a rather interesting find since using the bare infinitive in the active sentence does NOT seem to fit the rest of the sentence in terms of time OR meaning:

- People saw the system benefit the Soviet Union  (In my opoinion, this wording is wrong because the meaning is not quite what was intended.)
- People saw the system as (being) beneficial to the Soviet Union  (This wording is correct in my opinion.)

3. He was seen to cast frequent despairing glances at the sky.
This example is more like the sentence you asked about, Nessie.  I could form an active sentence this way:
People saw him cast frequent depairing glances at the sky. 

If I reword the active sentence (above) as follows, there is no difference in the basic meaning.  There is only a little bit more of a sense of action:
People saw him casting frequent depairing glances at the sky.

In short, I don't think it's worth worrying about your particular sentence because the active sentence is not very appropriate for an active/passive transformation exercise.

I'm glad you defended the teachers. After all, teachers sometimes find themselves in the awkward position of having to defend poorly conceived grammar exercises.  

By the way, I agree with your observation that "He was seen to steal ..." sounds like something that might turn up in a legal context.  I'm just not sure that "He was seen to steal your car" would be the way a formal and impersonal legal sentence would end. To me, the use of 'your' tends to make the sentence sound more personal and therefore less likely to be found in an impersonal legal context.

I hope somebody from the UK posts something here. I'd be interested in knowing whether either 'be let to do something' or 'be let do something' would sound  natural to British ears.