Feathers fall to the ground slowly,________ stones fall much faster.
| A．but | B．however | C．while | D．yet |
. Mary had taken _____ to see that her guests had everything that they could possibly want.
| A．efforts | B．pains | C．attempts | D．endeavors |
Although John was the eldest in the family, he always let his sister _____ charge of the house.
| A．take | B．hold | C．make | D．get |
. It isn’t so much whether he works hard; the question is whether he works _____.
| A．above all | B．in all | C．at all | D．after all |
The island where these rare birds nest has been declared a _____.
| A．observation | B．reservation | C．preservation | D．conservation |
Expected noises are usually more _____ than unexpected ones of the like magnitude.
| A．manageable | B．controllable |
| C．tolerable | D．perceivable |