I think this is a very basic grammar question, but I'm stuck with how I should continue the sentences.
Could you explain it?
1) In Japan, I've never shopped at a wholesale store, but I `did / did it / did so` a lot in the States.
2) I used to read books almost everyday, but now I `do / do it / do so` only once a week.
About the sentence 2, I know that I can say, " but now only once a week." But I'd like to know which is the best if I give a full sentence.