A. is
B. are
C. was
D. were
A. both
B. until
C. neither
D. either
A. comb
B. combs
C. combed
D. combing
A. learn
B. learns
C. learned
D. learning
A. buys
B. bought
C. buy
D. buying
A. did
B. does
C. do
D. had
A. is
B. are
C. was
D. be
A. leaves
B. left
C. had left
D. has left
A. go
B. goes
C. went
D. gone
A. has
B. have
C. had
D. having