为了提高传热效率，采用蒸汽加热时必须不断排除冷凝水并及时排放不凝性气体。
参考答案：对
It is in their ability to speak ______ humans ______ from animals. [ ]
A. which; differ
B. that; different
C. that; differ
D. which; different
下列各项中不属于甲状腺功能减退症临床表现的是
A．皮肤干燥B．食欲亢进C．记忆力减退D．畏寒E．声音嘶哑、低沉
