易燃液体是（）
A．苦味酸
B．乙醚
B．亚砷酸及其制剂
D．盐酸
E．氯化钾
参考答案：B
– Is your brother going to Jack’s birthday party tonight?
– I am not sure. He _____ go to the concert with his girlfriend instead.
A．ought to
B．has to
C．might
D．must
一般足球比赛，每队至少七名球员下场方可进行比赛。
