PET Writing Part 1

Here are some sentences about seaside holidays. For each question, complete the second sentence so that it means the same as the first, using no more than three words.
1) Mark couldn't lift the suitcase, he was too weak.

Mark wasn't lift the suitcase.
2) "Why don't we go to the beach?", I said.

I suggested to the beach.
3) There was nobody on the beach when we arrived.

There wasn't on the beach when we arrived.
4) Susan couldn't swim as well as Betty.

Betty than Susan.
5) I last saw dolphins when I was a child.

I haven't I was a child.