The teacher said we____ten lessons by the end of this term.

A．should have studied

B．were going to study

C．have studied

D．should study

探放老空水钻孔接近老空，预计有瓦斯或其他有害气体涌出时，必须有瓦斯检查员或（）在现场值班，检查空气成分。

A、班组长

B、安监员

C、工长

D、矿山救护队员