新掘巷道与原有巷道的方位要保持较大的夹角(最好大于45°)。
参考答案:对
The famous writer _____ one new book in the past two year.[ ]
A. is writing
B. was writing
C. wrote
D. has written
胆红素在血清中主要与哪种血浆蛋白结合()
A.γ-球蛋白
B.清蛋白
C.β-球蛋白
D.α1球蛋白
E.α2球蛋白