巷道主要有那些支护形式()。
A.木支架
B.金属支架
C.砌硂支架
D.锚喷支架
参考答案:A, B, C, D
He is even _____ than his brother. [ ]
A. funny
B. fun
C. funnier
D. more funny
肌肉长度--张力关系