问题
单项选择题
用于现浇混凝土空心楼盖的混凝土强度等级：钢筋混凝土楼盖不宜低于（），预应力混凝土楼盖不宜低于（），且不应低于（）。
A.C30、C50、C40
B.C25、C50、C35
C.C30、C40、C35
D.C25、C40、C30
答案
参考答案：D
搜题请搜索小程序“爱下问搜题”
用于现浇混凝土空心楼盖的混凝土强度等级：钢筋混凝土楼盖不宜低于（），预应力混凝土楼盖不宜低于（），且不应低于（）。
A.C30、C50、C40
B.C25、C50、C35
C.C30、C40、C35
D.C25、C40、C30
参考答案：D
A man was walking through a forest. He was holding an axe（斧子）in his hand. A little tree stopped him and said, “Please use your axe to those tall trees, my friend. Because of them, the sunlight cannot fall on me, and I have no room, at all to spread myself. them, I’ll be the pride of this part of the forest these years.”
The man decided to help the little tree. He used his to cut down the trees. Then the little tree had enough room. The little tree felt happy and said to the man. When the sun came out, the little tree lost water and it became very . Later when a storm came, the little tree all its leaves and branches（树枝）.
“Oh, poor little tree!”a bird said, ”You shouldn’t have asked the man to cut down the . The tall trees protected you you didn’t worry about heat or wind and rain. Time went by and you have . When you get all and , you can have enough strength to fight against the sun and the storms. So I don’t think you should do that.”
After hearing the words of the bird, the little tree felt regretful（后悔的）.
| 小题1: | A．put down B．cut down C．put off D．set off |
| 小题2: | A．With B．Without C．Because of D．As for |
| 小题3: | A．knife B．hand C．axe D．rope |
| 小题4: | A．sorry B．thanks C．no D．hello |
| 小题5: | A．thirsty B．hungry C．happy D．Sad |
| 小题6: | A．loved B．lost C．caught D．threw |
| 小题7: | A．grass B．plants C．trees D．forests |
| 小题8: | A．although B．while C．if D．so that |
| 小题9: | A．grown up B．got up C．used up D．stayed up |
| 小题10: | A．weak B．low C．short D．Strong |