_____ if he had any difficulties, he made no answer.
| A．Ask | B．To ask | C．Asked | D．Asking |
--- Shall we go for a drink at one o’clock this afternoon?
--- . Will two o’clock be OK?
| A．Sure, it’s up to you |
| B．Sure, no problem |
| C．Sorry, I can’t make it |
| D．Sorry, I’m not available today |
Scientists study ____ human brains work to make computers.
| A．when |
| B．how |
| C．that |
| D．whether |
The notice came around two in the afternoon____the meeting would be postponed.(2012•江苏)
| A．when |
| B．that |
| C．whether |
| D．how |
____medicine works in a human body is a question ____ not everyone can understand fully.
| A．How; that |
| B．That; which |
| C．What; which |
| D．What; that |
The media today can draw government’s attention to ____help is really needed.
| A．that |
| B．which |
| C．where |
| D．whose |