Errors in English usage

At the beginning everybody put their money into internet enterprises.

I would like to express my thankfulness to you for your business.

The point of these events is to give colleagues a chance to recognize each other better.

It's absolutely no good asking me. I haven't the smallest idea.

Probably the most interesting meeting of the whole week was the one when everybody had the opportunity to take portion.

There was such overwhelming support for the sitting on psychology that the organisers decided to repeat it in the evening.

I think that this probably has something to do with my jeans.

The scheme was to try and rise the morale of the workers and make them feel more cheerful.

I'm sorry but however persuasive you are, you just can't convict me that you are telling the truth.

The roll of the teacher as I understand it, is to help their students to think for themselves.