There are eight tips in Dr Roger’s lecture on sleep, and one of them is：_______to bed early unless you think it is necessary．

1. A.
   doesn’t go
2. B.
   don’t go
3. C.
   not going
4. D.
   not to go

There are eight tips in Dr Roger’s lecture on sleep, and one of them is: _______ to bed early unless you think it is necessary.

A. doesn’t go  B. not to go   C. not going   D. don’t go

There are eight tips in Dr Roger’s lecture on ―sleep, and one of them is :     to bed early unless you think it is necessary.

A. doesn’t go    B. not to go     C. not going       D. don’t go