The pipes have oil or water, which is heated and sent to the storage tank until to produce electricity.
| A．needed | B．needing |
| C．to need | D．having needed |
— Have you been here before?
— Yes. This is the third time that I ______ to Shanghai.
| A．come | B．came | C．have come | D．had come |
The number of the teachers who ______ cars in our school ____ increasing very fast.
| A．own; is | B．owns; is | C．own; are | D．owns; are |
I hadn't seen her for 10 years, but I ____ her at once.
| A．realized | B．recognized | C．knew | D．found |
——What a fine day! Shall we go picnicking?
——______. But we need to be home before six o’clock for the football match.
| A．Have a nice time | B．Pardon me | C．That’s great | D．You are right |
It was freezing last night, so they had the fire___ all night long.
| A．to burn | B．burned | C．burn | D．burning |