蛋白质工程的实质是[ ]
A.改造蛋白质
B.改造mRNA
C.改造基因
D.改造氨基酸
答案:C
以下关于各类民事法律行为之间关系的表述中正确的是( )。
A.双方民事法律行为都是双务民事法律行为
B.单务民事法律行为都是单方民事法律行为
C.有偿民事法律行为都是双务民事法律行为
D.实践性民事法律行为都是要式民事法律行为
They planned to go to Guangzhou to watch the Asian Games, but because of their daughter's unexpected
illness they had to stay at home ____. [ ]
A. otherwise
B. anyhow
C. however
D. instead