The old man isn't strong. He can't walk by him self. Why don't you tell her about your problem?

1. The old man isn't strong. He can't walk by him self
->......................................................................................... ( enough)
2. Why don't you tell her about your problem?
I think you should ................................................
3. She plans to learn Japanese next summer.
-> She is ........................................................
4. They didn't go the beach because it rained all day and night.
-> Why ................................................?