16. _______ medicine works in a human body is a question _______ not everyone can understand fully.
| A．How; that | B．That; which |
| C．That; which | D．What; that |
The bird was so lucky that it missed
| A．catching | B．to catch | C．to be caught | D．being caught |
— Have you heard me?
— I’m sorry, I youto me.
| A．don’t know, are speaking | B．didn’t know, were speaking |
| C．don’t know, were speaking | D．didn’t know, are speaking |
You had better book rooms at the hotel in advance you should find no room on your arrival.
| A．so that | B．even if | C．in case | D．now that |
There are lots of problems in your hometown, but we're happy to see many of them________.
| A．are solving | B．are solved | C．have solved | D．are being solved |
Everyone is different and that is ________ makes our world so much better.
| A．that | B．which | C．what | D．who |