太阳系是由以下哪些物质构成的?()
A.太阳
B.行星
C.彗星
D.星际物质
参考答案:A, B, C, D
_____ you read the sentences , _____ mistakes you’ll make.
A.More carefully, fewer
B. The more carefully, the less
C.The more careful , the fewer
D.The more carefully, the fewer
液压舵机液压油温度一般不允许超过()。
A.50°C
B.60°C
C.70°C
D.80°C