d me that he had two girl-friends,and neither of _______ knew anything about the other

Being _______, the novel written by a famous teacher sells _______.

I made a promise to myself________this year，my first year in high school，would be different.(2012·浙江，4)

I have great difficulty figuring out the answer to this problem. — _____ my advice, you ____ less difficulty with such problems.

Lucy ________ guitar lessons every three weeks in the past three years, but now she is considering she’ll make it every other week