__________ with the size of the whole earth，the highest mountain doesn’t seem high at all.
| A．When compared | B．To compare |
| C．While comparing | D．It compared |
There were some chairs left over ______everyone had sat down.
| A．when |
| B．until |
| C．that |
| D．where |
--Mom, what did your doctor say？
--He advised me to live____the air is fresher.
| A．in where |
| B．in which |
| C．the place where |
| D．where |
Please remind me______he said he was going.I may be in time to see him off.
| A．where |
| B．when |
| C．how |
| D．what |
It is none of your business other people think about you.Believe yourself.
| A．how |
| B．what |
| C．which |
| D．when |
Having checked the doors were closed, and all the lights were off, the boy opened the door to his bedroom.
| A．why |
| B．that |
| C．when |
| D．where |