1. The door was so heavy that the boy couldn't open it.

⇒ It was such a heavy door that the boy couldn't open it.

2. If you solve the prolem soon, it will be better for you.

⇒ The sooner you solve the problem, the better it will be.

3. I find it easy to drive a car.

⇒ I have no difficulty in driving a car.

4. It took me six hours to fly from VietNam to America.

⇒ The flight from vietnam to america lasted six hours.

5. He doesn't like coffe and neither do his friends.

⇒ Neither he neither he nor his friends likes coffee.

`(1.)` It was such a heavy door that the boy couldn't open it.

`(2.)`The sooner you solve the problem, the better it will be.

`(3.)` I have no difficulty in driving a car.

`(4.)` The flight from vietnam to america lasted six hours.
`(5.)` Neither he neither he nor his friends likes coffee.