The police have caught the suspect and he immediately admitted______his boss on a rainy night seven years ago.
A. to kill
B. to have killed
C. having killed
D. have been killed
查看答案
在消耗ATP的情况下,电子可从复合体Ⅳ流动到复合体Ⅰ。()
A. 正确
B. 错误
I would have gone to the hospital to visit him had it been possible, but I______fully occupied last week.
A. were
B. has been
C. have been
D. was
Before the invention of refrigeration, the______of fish and meat was a problem.
A. keeping
B. preservation
C. maintenance
D. protection
Don't stay______too late, or you'll be sleepy in class tomorrow.
A. on
B. out
C. up
D. for