正常启动前，操作人员必须发出启车信号，时间不得少于（）min。
A.2
B.3
C.4
D.5
参考答案：A
Read and match. (读短文，连线)
Jack, Li Ming, Xiaohong and Lily are good friends. They went to a pond to fish. Jack's fish is
heavier than Xiaohong's. Lily's fish is shorter than Li Ming's. Lily's fish is smaller than Xiaohong's.
Li Ming's fish is longer than Jack's. Can you find their own (自己的) fish？
Jack LiMing Xiaohong Lily
A. B. C. D.
5kg 30cm 4kg 50cm
为了有计划地进行生产操作和检修焦炉机械，生产中要建立（），便于检查焦炉生产的情况。
B. 
C. 
D. 