Помогите поставить глагол в правильную форму. Предложения с 4 по 20

4) if I see, Ill tell
5) will buy, I ask
6) what will you do, you fail
7) who will help, youre in difficulty
8) mum likes, she will let
9) Ill take, it rains
10) she will learn, she has
11) will you forgive, if you know
12) if its cold, Ill put
13) plane arrives, Ill come
14) if you are out, Ill leave
15) we will watch, if you recommend
16) if he has, he will go
17) if there is, we will eat
18) if it is, we will go
19) Ill let you know, we decide
20) if she stays, she will cook