I'd be happy if someone would answer my questions. Thanks in advance.

Q 1  Are the following 3 sentences grammatically right and the same in meaning?

A:  I've been here since 7 o'clock.

B:  I've been here from 7 o'clock on.

C:  I've been here from 7 o'clock.

Q 2  Are the following 3 sentences grammatically right and the same in meaning?

D:  I've been here since I came back.
    
E:  I've been here from the time I came back.

F:  I've been here from when I came back.

Hi Doll,

Why are you so sure these other examples are wrong?

For example if, as you say, 'since' means 'from a particular time',  you wouldn't accept 'from 7 o'clock'? Isn't 7 o'clock a particular time?

Best wishes, Clive

Magic-dragon wrote:

I'd be happy if someone would answer my questions. Thanks in advance. Q 1  Are the following 3 sentences grammatically right and the same in meaning? A:  I've been here since 7 o'clock. B:  I've been here from 7 o'clock on. C:  I've been here from 7 o'clock. Q 2  Are the following 3 sentences grammatically right and the same in meaning? D:  I've been here since I came back.      E:  I've been here from the time I came back. F:  I've been here from when I came back.

Magic-dragon,

Grammatically and idiomatically speaking, only A and D are the correct answers. Based on your sentences, "since" is correct choice, although "from" is possible for Q-E. but less preferred in my opinion. i.e. I have been working here since I came back from England vs.  I have been working here from the date I came back from England...

A:  I've been here since 7 o'clock.

B:  I've been here from 7 o'clock on.

C:  I've been here from 7 o'clock.

Q 2  Are the following 3 sentences grammatically right and the same in meaning?

D:  I've been here since I came back.
    
E:  I've been here from the time I came back.- Possible

F:  I've been here from when I came back.

I must admit, to me, all the sentences look ok:

A:  I've been here since 7 o'clock.

B:  I've been here from 7 o'clock on.

C:  I've been here from 7 o'clock.

D:  I've been here since I came back.
    
E:  I've been here from the time I came back.

F:  I've been here from when I came back.

For me, #A looks back to 7 o/c from "now", while #C looks forward to "now" from 7 o/c (i.e. the difference is one of perspective). #B emphasises the "looking forward from 7 o/c".

Similarly for #D ("since") and #E/#F ("from").

(Other speakers might well have a different interpretation, though.)

MrP