Be careful! Sometimes is the only adverb of frequency that can also go at the beginning of a sentence.
Be careful with negatives! They still go before the verb.
I usually eat lots of fruit. → I don’t usually eat lots of fruit.
In English, you can only have one negative form in a sentence. So, if you use never or hardly ever, the auxiliary (don't/doesn't) is not used.
a. I hardly ever eat cheese. c. My sister never eats meat.
b. I hardly ever don’t eat cheese. d. My sister doesn’t never eats meat.