Complete the second sentence so that it has the same meaning as the first one

Complete the second sentence so that it has the same meaning as the first one.  
1. I don't have so many friends. -> I have...................
2. My brother drinks more coffee than my sister.
-> My sister drinks.............................................
3. It is necessary to learn English well. -> Learning........
4. We should get up early every day. -> We shouldn't...............
5. How wide is this room? -> What...............................
6. Don't forget to lock the door before you leave.
-> Be sure...................................