________her home, Mary helps her mother with some housework.
| A．As soon as she returns | B．On arriving |
| C．After she gets | D．Immediately she reaches |
__________ matters most in learning English is enough practice.
| A．What | B．Why |
| C．Where | D．Which |
Choosing the right dictionary depends on __________ you want to use it for.
| A．what | B．why |
| C．how | D．whether |
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．ours |
It is none of your business __________ other people think about you. Believe yourself.
| A．how | B．what |
| C．which | D．when |
You can only be sure of __________ you have at present; you cannot be sure of something __________ you might get in the future.
| A．that; what | B．what; / |
| C．which; that | D．/; that |