中小型冲裁模的上模固定在冲床滑块上,是通过()实施的。
A、导板
B、导柱和导套
C、压板
D、模柄
参考答案:D
_____ no need to worry about the problem.The government has promised to have clean water _____ to us from door to door.
A.It is ; delivered
B.It is ; delivering
C.There’s ; to deliver
D.There’s ; delivered
流行性乙型脑炎是由乙脑病毒引起的急性中枢神经系统传染病,一般流行于().
A.春夏季
B.夏秋季
C.秋冬季
D.冬春季