鼓风机系统故障,风阀跳动、失调是造成燃烧不稳定的原因之一.
参考答案:对
— Why do you always go to Zhejiang University on weekends?
— Because there’re lots of great speakers I can practice English in the English Corner there.
A.to
B.with
C.on
D.About
伤寒患者出现玫瑰疹,多见于
A.潜伏期
B.发病初期
C.高热期
D.缓解期
E.恢复期