The professor’s research finally proved to be ______, though he had spent a lot of money on it.
| A．priceless | B．valuable | C．worthless | D．worthwhile |
“Mum, why do you always make me eat an egg every day?” “_____enough protein and nutrition as you are growing up.”
| A．Get | B．Getting | C．To get | D．To be getting |
A broad smile spread_____ Jack’s face when he eventually gained a scholarship.
| A．across | B．through | C．at | D．in |
China’s Beidou global satellite navigation system will have been completed by 2020, ____ of more than 30 satellites.
| A．consisting | B．consisted | C．to consist | D．consists |
Such a fierce dog _____ that we had to wait outside before we could get into his yard.
| A．has he had | B．did he have | C．he has | D．he has had |
An independent traveler would like to struggle with maps and signs ____ he finds the way．
| A．since | B．until | C．before | D．when |