Ladies and gentlemen please fasten your seat belts. The plane .A. takes offB. is taking o

问题补充：

Ladies and gentlemen, please fasten your seat belts. The plane .

A. takes off

B. is taking off

C. has taken off

D. took off

答案：

A. takes off

(答案→)B. is taking off

C. has taken off

D. took off

解析：考查时态。用现在进行时表将来。