State the composite sentences:
1. It will be remembered that some hypotheses were put forward in the
last decade.
2. He knew that they would search the area where they had lost him.
3. The brave don't lay down their arms.
4. Whether he will agree is another question.
5. One of the goals of education is to bring people together.
6. It is doubtful whether the payment is strictly legal.
7. Over the last hundred years further energy supplies have evolved,
especially in advanced regions,
8. How it has been done does not matter.
9. The thought that his younger sister was unhappy kept him awake all the night.
10. In the backyard, the dog barked and howled at the cat.