A．terribleB．aspectC．respectD．mathematics
A. terrible
B. aspect
C. respect
D. mathematics
A．importantB．reliableC．sadD．acceptable
A. important
B. reliable
C. sad
D. acceptable
What do we learn about a stem cell？
A. It has no difference from other cells.
B. It can only become a certain type of cell.
C. It can't become a kidney cell.
D. It maintains and repairs the body.
按照我国的有关规定，国际货运代理企业从事航空运输销售代理活动，应当取得中国航空运输协会颁发的资格认可证书。()
A. 正确
B. 错误
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