grammar in English

^ I think "You're right" or "It's a good ideal" is better, "Also true" seems to be dull of meaning.

You just say a sentence about any topic there. Excellent English learners will help you correct the error that you have to (if any).

"You just need to say a sentence about any topic in there" is fixed in grammar, but to correct, you should replace "in there" by "in here/at here" or "in this thread".

A small essay or passage about a topic seems to be more interesting . I mean there will be more error to correct, and, , moreover,we can practice to write

Write whatever you want, even just a short sentence, but of course, must be in English =).

i think in ur sentence after "should" it's must be "use" not "uses" am I right?

Correct. Heheh, bad habit.