Упражнение

a) go — …
b) come — …
c) bring — …
d) do — …
e) write — …
f) read — …
g) be — …
h) take — …
i) give — …
j) put — …
k) swim — …
l) buy — …
m) sell — …
n) say — …
o) tell — …
p) pay — …
q) understand — …
r) think — …

a) go — went — gone
b) come — came — come
c) bring — brought — brought
d) do — did — done
e) write — wrote — written
f) read — read — read
g) be — was, were — been
h) take — took — taken
i) give — gave — given
j) put — put — put
k) swim — swam — swum
l) buy — bought — bought
m) sell — sold — sold
n) say — said — said
o) tell — told — told
p) pay — paid — paid
q) understand — understood — understood
r) think — thought — thought