The hottest continent, Africa has a lot of resources, ______ are still undeveloped.
| A．many of them | B．many of whom | C．many of it | D．many of which |
Since entry into high school the students have been ____ staying up late in the evening and getting up early in the morning.
| A．admitted to | B．allergic to | C．accustomed to | D．attached to |
—Was it under the tree _______ you were away talking to a friend?
—Sure. But when I got back there, the bike was gone.
| A．that | B．where | C．which | D．while |
----How did you like Nick’s performance last night? ----To be honest, his singing didn’t _______to me much.
| A．appeal | B．belong | C．refer | D．occur |
Some insects ______ the colour of their surroundings to protect themselves.
| A．take in | B．take off | C．take on | D．take up |
Mothers holding jobs outside the home should have _______ schedules to make it easier to care for their children.
| A．heavy | B．smooth | C．flexible | D．complex |