Ответ:
15 - will give, work
16 - don`t do,will win
17 - arrives,shall have to
18 -wonder,will follow
Объяснение:
15. Your boss will give you the day off on condition that you work on Saturday morning.
16. Provided that they don't do anything stupid, they will win tonight's match easily.
17. Unless he arrives soon, we shall have to go without him.
18. I wonder if they will follow our advice.