关于青藏地区的叙述正确的是(    )
①干旱为主的自然特征
②河流较少，多为内流河
③具有丰富的太阳能资源
④很多山峰终年积雪，冰川广布

王安石曾感叹：“京口瓜洲一水间，钟山只隔数重山。”进入21世纪，哪一座桥梁的修建结束了京口与瓜州的一水相隔。（    ）

阅读下文，回答问题
                                                                                                  On the beach
    It is a fine day. A lot of people go to the beach to enjoy sunshine. Some people are swimming like fishes in the sea. On the beach，some young people are playing volleyball.
    Some of them are lying under the coconut trees. And some old people are chatting with each other. What are the children doing? Look! They are making castles with spade and sand. They are having fun。
⑴⑵⑶⑷⑸根据短文内容，判断正误；⑹根据短文内容填空。

下列四幅地形剖面示意图，能正确表示我国地势变化的是（　　）

下列关于生物进化总趋势的叙述,不合理的是（    ）