自然界中存在氧循环和碳循环，其中能将二氧化碳转化为氧气的是 [ ]
A. 燃料燃烧
B. 动物的呼吸作用
C. 植物的呼吸作用
D. 植物的光合作用
答案：D
填空题
1. In general, girls are much____ (hardworking) than boys.
2. This village is____(quiet) during the day than at night.
3. It's one of____ (meaningful) activities in this term.
4. My fingers are ____long ,but Tom's are ____longer than mine.( very ,much)
5. He ate (much too ,too much) cold food yesterday evening.
扁钢接地体的焊接应采用搭接焊，其搭接长度必须为其宽度的（）倍。
A.3
B.2
C.4
D.6
