A. went B. go C. gone D. goes
A. has; saw B. has; seen C. did; see D. have; seen
A. did learn B. were learning C. have learned D. learn
A. fails B. fail C. failed D. is failing
A. Has; started B. Did; start C. Was; starting D. Is; starting
A. is B. are C. be D. has
A. Go back B. Turn on C. Turn D. Come
A. cheaper B. cheap C. cheapest D. more cheap
A. much beautiful B. more beautiful C. beautiful D. some beautiful
A. better B. worse C. the best D. the better
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