土方工程施工过程中，土壁的稳定，主要依靠土体的（）。
A.内摩擦力
B.密实度
C.黏结力
D.吸附力
参考答案：A, C
The science of computer, _______rapid progress has been made in recent years, is the most important of all science.
A．which
B．with which
C．in which
D．to which
肺气上逆的表现，主要是
A．恶心、呕吐
B．呃逆、嗳气
C．吐血、咯血
D．咳嗽、气喘
