分析环渤海地区内河航运不够发达的自然原因。
参考答案:
①河流水量小,且流量季节变化大;②河流含沙量大,航道容易淤积;③河流有封冻现象;④河网密度较小,通航里程短。
用括号内所给词的适当形式填空
1. I have some nice______( picture) .
2. Please bring your math book to_____(I).
3. Some plants ______(be) on the table.
4. —Where are ______( you) video tapes?
—They are on the dresser.
5. Can you ______ (take) Tom to school?
6. This is my ______ ( sister) room.
7. These are my ______ (key).
8. ______ (be) your pencils on the desk?
9. Sorry. I don't know ______ (she)name.
10. —Where are the books?
— _____ (it) are in the drawer.
小黄、小白、小蓝三人相遇在火车站,忽然他们中间提着白色提包的一个人说:“真是有趣,我们三个人的手提包,一个是白的,一个是黄的,一个是蓝的,可是没有一个人的手提包颜色跟自己的姓相同。”小黄立即接着说:“是啊!”请问:护士小蓝的提包是什么颜色的.()
A.黄色
B.白色
C.蓝色
D.绿色