These are my questions. Can you help me, please?

As he was taking a shower,
the water finished. (is it correct to say ...
the water finished?)
As I was on a diet, I was
prohibited from eating any fried food. (is it correct to write: ..I was
prohibited from...?)
Whenever we make
a blood transfusion, lives are saved. (is the correct :...
make a blood transfusion or
blood transfusion? )
Whenever the lift is out of order, they have to take the stairs. (is it correct to say:
to take the stairs?)
“That’s right. They didn’t walk on the beach because of the
sticky sand.” (is it correct: “
sticky sand”?)“That’s right He isn’t going to make the furniture because of the rotten logs.” (
is this sentence O.K.?)
I’ll
hand in the composition whether it is ready or not. (is it correct to say:
hand in as a synonym of
deliver in hands, give?)
Thank you a lot!

Ashley