777.I haven't got the reference book yet,but I'll have a test on the subject next month.
Don't worry.You ______ have it by Friday.
A.could
B.shall
C.must
D.may
778.I have told you the truth._______I keep repeating it?
A.Must
B.Can
C.May
D.Will
777.答案是B;shall在第二，三人称的陈述句中表许诺，命令，威胁，警告，还可用于法律条文的要求或规定。
778.答案是A;我已经告诉了你真相，还用重复吗?
