Don't ______.You will ______ new customs and different ways of thinking.
| A．lose your heart；apply to |
| B．lost heart；apply yourself to |
| C．lose your heart；adapt to |
| D．lose heart；adapt yourself to |
within
| A．depth | B．youth | C．bathe | D．wealth |
around
| A．tough | B．count | C．cough | D．routine |
cheese
| A．radios | B．aside | C．adjust | D．diverse |
wander
| A．absorb | B．wallet | C．village | D．salary |
_________ that causes heavy haze sweeping over china remains unknown to many scientists.
| A．what it is | B．what is it |
| C．who is it | D．who it is |