轴瓦在厚（）薄钢背的内圆面上浇铸减磨合金层。
A.0.1～0.3
B.1～3
C.1～2
D.3～4
参考答案：B
In the picture, between two closely-located buildings____ a big tree.[ ]
A. grow
B. grows
C. has grown
D. have grown
哈德良长城在哪个国家（）。
A.中国
B.法国
C.英国
