Many _______ of years later, the first extremely small plants began to appear on the surface of the water.
| A．millions | B．million | C．million of | D．millions of |
I’m not sure whether I will have anything else to do this evening．_____, I will try every possible means to come to your birthday party．
| A．Even though | B．If so | C．Anyhow | D．Instead |
My toothache is killing me．I _____ it _____ away．But now it’s getting worse and worse．
| A．think; is going | B．thought; was going |
| C．have thought; is going | D．had thought; had gone |
---The exam starts at 9:00 tomorrow morning．
---___________ I fail to arrive there on time?
| A．What if | B．As if | C．Only if | D．Even if |
_____ on May Day, the Shanghai Expo has attracted tens of thousands of visitors around the world every day．
| A．Having opened | B．Opened |
| C．Opening | D．To open |
With the moonlight keeping them ________, the tourists climbed over the mountain without a guide．
| A．approach | B．silence | C．secret | D．company |