管线热水预热的方法不包括()。
A.正向预热
B.反向预热
C.正反向同时预热
D.从中间预热
参考答案:D
The teacher just took down the names of the students _______ during the exam.
A.caught cheating
B.caught to cheat
C.catching cheating
D.to catch cheating
固体废弃物样品经105℃烘烤、粉碎后,不适合分析的项目是()
A.铅、镉、砷
B.总汞
C.有机磷
D.全量金属
E.氰化物