根据首字母及句子意思补全单词，使句子意思连贯、语法正确。

1. Look at the sky! The kites are flying so h              that they look like small birds.

2. — Excuse me. How can I get to the post office?

    — Go down this road until you see a tall building. You can't m              it.

3. Mum, I'm h             after a long run. Please give me something to eat.

4. — I advise doing something to relax ourselves after the exams. Do you a              with me?

    — Yes, but how?

5. Most Chinese have three m             a day. They are breakfast, lunch and supper.

下列叙述正确的是[ ]

A．湖水富营养化可使水草和藻类大量繁殖，并通过光合作用产生大量氧气

B．温室效应可以使全球更加温暖，有利于人类的生存

C．我国西部实行“退耕还林还草”政策是因为西部耕地过剩，森林、草地不足

D．盲目引进外来生物很可能破坏当地的生态平衡