The tomato juice left brown ____ on the front f my jacket．
| A．spots | B．points |
| C．tracks | D．traces |
No one really knows exactly dfwhen the first people arrived in______we now know as California
| A．what | B．when | C．where | D．which |
I'll bring some medicine jus______some of us get sick while travelling．
| A．As if | B．in case | C．even though | D．as long as |
—Have you found the missing?couple in the mountain ?
—No, but we______hard to get in touch with them．
| A．have tried | B．have been trying | C．had tried | D．had been trying ． |
The average temperature in．Tibet has risen______ 0.32 degrees centigrade every decade since 1961, according to the China Meteorological Administration,．
| A．to | B．at | C．by | D．in |
—On which day shall we go outing in the Qiagling Mountains, Friday, Satutiby or Sunday?
—______is all right.
| A．Either | B．Both | C．All | D．Any |