1) дайте развернутые ответы на следующие вопросы, обращая внимание на употребление времен в придаточных времени и условия. 1. will you sign contracts if they give you a good discount? 2. what will you do tomorrow after you look through the documents? 3. will you introduce mr. hunt to your sister if he is single? 4. what will you do if you have a toothache? 5. will they only have to pay for their phone calls to their local service providers when they send e-mail messages? 6. what shall we clear up before he leaves? 7. will you get in touch with them if they deliver the goods?

1) I will sign contracts if they give me a good discount
2) I will go for a walk after I look through the documents
3) I will  introduce Mr. Hunt to my sister if he is single
4) If I have a toothache, I will go to the dentist
5) When they send e-mail messages, they will only have to pay for their phone
calls to their local service providers
6)     Before he leaves, we shall clear up the kitchen.
7) If they deliver the goods, we will get in touch with them
Здесь смысл в употреблении conditionals. После conditionals не должно быть будущего времени. Будущее время в другой части предложения, не после conditionals.
Успехов Вам!