Present Perfect Exercises

Supply the Simple Past or the Present Perfect Tense of the verbs
in the parentheses:
a) I ____________________________ have finished
my homework. ( to
finish)
b) When I was a boy, I _________________________ swam
in
the river. ( to swim)
c) She _________________________ met
all her friends last
weekend. ( to meet)
d) He ____________________________ bought
that old car two
years ago. ( to buy)
haven‘t taught
e) We ____________________________ this exercise before.
( to teach)