多层涂装时,要注意它们之间的附着性和互溶性。()
参考答案:对
空预器入口二次风温低于()时应投入暖风器运行。
In autumn in the north of the earth the days get ____ and the nights get ____.[ ]
A. tall; short
B. short; tall
C. longer; shorter
D. shorter; longer