If _____, please buy me a backpack while
问题:
If _____, please buy me a backpack while you are at the supermarket.
A.you are convenient
B.it is convenient to you
C.it is convenient with you
D.I am convenient to you
If _____, please buy me a backpack while you are at the supermarket.
A.you are convenient
B.it is convenient to you
C.it is convenient with you
D.I am convenient to you