Only after leaving home ________ the true meaning of the proverb, “East or west, home is best.”
| A．he understood | B．he did understand |
| C．did he understand | D．had he understood |
--- It’s the fourth time that heavy smog(雾霾) has hit the city this month.
--- It’s high time we _______ measures to fight air pollution.
| A．will take | B．took | C．to take | D．taking |
Science has given clear evidence ______ smoking can lead to many diseases.
| A．what | B．which | C．that | D．where |
We admire this family, ______ the parents treat their child like a friend.
| A．why | B．which | C．where | D．that |
The weather in Inner Mongolia is always dry, but sometimes it _____ rain heavily.
| A．need | B．can | C．must | D．shall |
No pleasure can equal ______ of having a good sleep after hard work.
| A．that | B．one | C．it | D．those |