помогите состовить трудные предложение со словами:because, as, since, because of, owing

I trust him because he is a good friend of mine.
I am not nervous at all as i have flown before.
I have been busy since 4pm.
It happened because of you.
The meeting has been canceled owing to lack of people.
We decided to stay here in order to help him.
The letter should be rewritten so as to be shorter.
He said that in order to make you laugh.
Her parent are very tall and, consequently, she is tall too.
He had not seen her in a while, as a result, he didn't recognise her.