According to a UN report，one third of the world population have no to clean drinking water and health care.
| A．means | B．approach | C．channel | D．access |
Sorry I’m so late, but you cannot imagine ________ great trouble I took to find your house.
| A．what | B．how | C．which | D．why |
Too high house prices can be brought under control, _______ the authorities introduce a series of regulatory policies.
| A．even if | B．as if | C．so that | D．provided that |
Occasions are quite rare ________ I have time to spend a day with my kids.
| A．who | B．which | C．why | D．when |
----English has a large vocabulary, hasn’t it?
----Yes. _____ more words and expressions will help you easily read and communicate.
| A．Know | B．Knowing | C．To know | D．Known |
My grandfather is fond of talking about the good old days, ________ is often the case with old people.
| A．when | B．as | C．that | D．what |