—I left my handbag on the train, but luckily someone gave it to a railway official．
—How unbelievable to get it back! I mean．someone _____ it．
| A．will have stolen | B．might have stolen |
| C．should have stolen | D．must have stolen |
In such a background, his white hair was particularlyhis dark skin．
| A．in relation to | B．in need of | C．in contrast to | D．in favor of |
The black baby boy is at the stagehe can only say a few simple words but not yet full sentences．
| A．when | B．where | C．which | D．why |
Up to now, no one has come up with a（n）explanation of why dinosaurs died out, and it remains a mystery．
| A．astonishing | B．amusing | C．convincing | D．puzzling |
All the cloned animals have so far suffered from some serious disorders, many ofdying soon after birth．
| A．that | B．whom | C．which | D．them ． |
Your IQ isn’t _____determines whether you will succeed in your future life.
| A．what | B．where | C．that | D．why |