问题:
________ have you written to your pen friend? Once a month.
A.How soon
B.How long
C.How often
D.How far
________ have you written to your pen friend? Once a month.
A.How soon
B.How long
C.How often
D.How far
A.How soon
B.How long
C.How often
D.How far
参考答案: