He made another wonderful discovery, ______ of great importance to science.
| A．which I think is | B．which I think it is |
| C．which I think it | D．I think is |
It was dark; we decided to for the night at a farm house.
| A．put away | B．put down | C．put up | D．put out |
He accidentally he had quarreled with his wife and that he hadn’t
been home for a couple of weeks.
| A．let out | B．took care | C．made sure | D．made out |
It’s ten years since the scientist on his life’s work of discovering
the valuable chemical.
| A．made for | B．set out | C．took off | D．turned up |
---What’s the matter with you?
---After the long walk, my legs and I couldn’t go any further.
| A．gave out | B．gave off | C．gave in | D．gave up |
When the right opportunity , she’ll take it.
| A．comes up | B．come across | C．comes along | D．comes to |