Find the one mistake in each sentence and then correct it

Find the one mistake in each sentence and then correct it:
1. He would have been angry if you had not talked him the truth.
2.Was she to see you, she would be very surprised ?
3. Unless your health improved, you would have to stay on bed ?
4. If she wrote more carefully, she might not have made so many mistakes.
5. Had I known she is sick, I should have visited her ?