A:①③
B:①④
C:②④
D:②③
根据句意及首字母填空。
⑴____A. morning B. good C. afternoon
⑵____A. friend B. sister C. brother
⑶____A. this B. I C. you
⑷____A. is B. am C. be
⑸____A. he B. she C. my
A traffic accident happened this morning. ____ (luck), no one was badly hurt.
下列生物中,哪一种是利用转基因技术培育出来的( )