我国许多大河滚滚向东流,这是因为[ ]
A.我国地势西高东低
B.我国地形复杂多样
C.我国东临太平洋
D.我国边缘海大陆架宽广
答案:A
观察下列图片,回答相关问题:
请回答:
—What's the boy doing?
—He's ______ his sweater. It's cold outside. [ ]
A. putting
B. putting on
C. wearing
D. in