1.
1. See saw seen
2. Find found found
3. Bite bit bitten
4. Buy bought bought
5. Come came come
6. Eat ate eaten
7. Lose lost lost
8. Sing sang sung
9. Forget forgot forgotten
10. Understand understood understood
11. Bring brought brought
12. Hold held held
2.
a) have visited
b) has tidied
c) have bought
d) has arrived
e) have talked
f) have studied
g) has passed
h) has slept
i) have barked
j) has bought
k) has took
l) has started
m) has came
