我国唯一注入北冰洋的河流是( )
A:雅鲁藏布江
B:澜沧江
C:额尔齐斯河
D:黑龙江
A:Our new school is big and nice. There is a gym in our school now.
B:Yes, and there is a big library, too.
课外拓展
学了《征友启事》这个故事,你们懂得了什么道理?
67 ÷7=____ 19×3 =____ 1+50%=____ 45×15 =____
34×15 ÷ 34×15 =____ 16 + 56 × 15 =____ 12 ×101- 12 =____ 34 ×9× 43 =____