seen to enter the room

[keannu]

Whenever I explain to my students, I always say the reason why "seen to enter" sounds awkward is because "to enter" has the nuance of a purpose like "in order to enter". Is it correct?
ex)He was seen to enter the room (vs) He was seen entering the room.

[konungursvia]

Entering is a deliberate act of volition, unless you say "stumbled into" or "wandered into" or some such thing. So, I see no difference between the infinitive and gerund here.

[keannu]

Entering is a deliberate act of volition, unless you say "stumbled into" or "wandered into" or some such thing. So, I see no difference between the infinitive and gerund here.

Then, I don't know why my grammar book says "seen to enter" is regarded as awkard by native speakers, Which do you hear or say more often? "to enter" or "entering"? I mean gerund or infinitive?

[5jj]

Then, I don't know why my grammar book says "seen to enter" is regarded as awkard by native speakers,

Neither do I. As COCA has just one example of each, neither is common; there is little point in worrying about it,

[keannu]

Neither do I. As COCA has just one example of each, neither is common; there is little point in worrying about it,

Before I went to Canada, I studied several grammar books saying "to infinitive" and "gerund" are both okay for passive tense, but after I got back, I bought this grammar book and reading the grammar, I felt the previous old books are all wrong.

I explained to my students that "to infinitive" in passive voice is awkward as it can mean a purpose sounding weird, but I wasn't hundred percent sure of it as I haven't had it verfied by native speakers.Now I feel guilty and came to distrust the part in the grammar book. Okay, I will forget it and just use the both as beforel.

[JMurray]

"seen to enter" reminds me of the kind of slightly stilted English that a police officer might use when giving evidence in court.
"The accused was seen to enter the room at 10:32 AM where she remained for approximately seven minutes. She appeared to acknowledge a second person whose identity remains unknown and who was holding a small parcel in his left hand. The accused was then seen to leave the room by the rear entrance carrying the aforementioned parcel, or one that was very similar. The contents of the parcel, or parcels, are yet to be ascertained".

not a teacher

[5jj]

"seen to enter" reminds me of the kind of slightly stilted English that a police officer might use when giving evidence in court.

That was my first reaction , but then I thought that it is probably the passive that makes it seem a little stilted. It just seems to be that active and passive equivalents use the same -ing forms, but different infinitive forms.

I saw him entering ... - He was seen entering ..........I saw him enter ... - He was seen to enter ...
I heard him shouting ... He was heard shouting ........I heard him shout ... - He was heard to shout ...