问题
The new School Safety Guidelines states that under no circumstances _______ leave the campus alone.
A:a student is to
B:is a student to
C:a student be to
D:be a student to
B:is a student to
C:a student be to
D:be a student to
正确答案是：
同类题型
Do you know if ________ tomorrow morning—No. I will call you if she ________ back.
.Nowadays .all passengers go through safety check before take a train.
The topic, _______ we devoted a heated discussion last night, is a hot issue at present.
___you understand this rule, you will have no further difficulty