explain

[nawab]

Dear all,
a student of 10th class asked me: 1) what is the function of 'by 'in passive voice. 2) i climbed a tree, was changed into passive, the tree was climbed by me. is it true. 3) a clear demarkation in transitve and intrasitive verbs.

kindly send me as soon as possible as i have to explain it tomorrow.
thanks
Nawab

[David L.]

An action (something a person does) is done "to" them, "by" somebody.
In active voice, the 'doer' is the subject:
John hit Bob - the action was done by John, to Bob
In the passive voice, the receiver of the action is placed first, in the subject:
Bob was hit by John.
the function of 'by', therefore, is to show who the "doer' of the action is;
just as 'to' tells us who or what was was on the receiving end of the action, to whom it was done

"the tree was climbed by me" is correct grammar.

I'm not sure what you are asking in (3)

[nawab]

Hi, define transitive and Intransitive verbs with examples, and also explain that there are some verbs that are used in both ways, how would we deffrentiate them.nawab

[Anglika]

Try looking through this: Verbs - Glossary Definition - UsingEnglish.com