Нужно вставить правильно preposition!

1 for

2 of

3 to

4 to(of)

5 of

6 for

1.There's no reason for you to be so unhappy.Cheer up!

2.In your next letter, I want you to give me a full description of your new house.Maybe you could send me some photos, too.

3. The earthquake that hit our town yesterday caused damage to lots of houses.

4.No matter how hard I try, I can't find the solution of this riddle.

5.James is really in need of money as he has to pay off a loan to the bank.

6. Man is the biggest thread for the environment.