A:
Regular verbs: to visit, to walk, to collect.
Irregular verbs: to take, to send, to drive, to spend, to know, to give, to have, to write, to go, to think.
B:
send — sent; drive — drove; spend — spent; know — knew; give — gave; be (am, is, are) — was, were; have — had; write — wrote; go — went; think — thought.