第7题: [单项选择]Every device______ in the spacecraft must be designed and made with great care so as to be sure that nothing goes wrong in operation. A. to be fitted B. fitted C. fitting D. to have been fitted 参考答案:A 答案解析:此处用不定式是指“(将)要装配在宇宙飞船上的每个器械必须精心设计制做..”,我们知道不定式与动名词的区别之一是不定式表示即将实现的动作,而动名词可以表示已实现的动作。另外不定式在句中作device的定
第13题:[单选题]When we were young, we ___________ to stay out after 11 o′ clock. A.hadn't allowed B.didn't allow C.weren't allowed D.wouldn't allow 参考答案:C 考查allow的被动语态。句意为“小的时候,我们不被允许晚上在外面待到十一点之后”。 allow的意思是“允许,许可”,根据句意这里应该用其被动语态的否定形式:be not allowed to do sth.“某人不被允许做某事”。故C正确。
第33题: [单项选择]已知混凝土的三轴应力状态为三向受压,应力比为:σ1:σ2:σ3=-1.0:-0.3:-0.15。试问下列各项中在三轴受压状态下混凝土抗压强度的提高系数何项正确 A. 2.3 B. 1.8 C. 2.0 D. 1.4 参考答案:A 答案解析:[解析] σ1:σ2:σ3=-1:-0.30:-0.15,因此σ2/σ1=0.3/1=0.