It’s not ___ good idea to drive for four hours without ___ break.
I was deeply impressed with the man’s willingness ______.
--Where did you put my dictionary after using it this morning? --I put it back ______ I took it.
The discussion came to life when someone ______ an interesting topic.
After the new technique was applied to production, the factory has produced ______ over the same period last year.
. -- What does the sign on the wall read? --“ No person ______ enter it without permission.”