他很小心,没有把真相告诉他的老板。
He was careful not to tell his boss the truth.
be careful 对…小心
单项选择。
— Happy New Year!
— ______. [ ]
A.Happy too
B.The same to you
C.Good
D.Good luck
若一个双链DNA分子的G占整个DNA分子碱基的27%,并测得DNA分子一条链上的A占这条链碱基的18%,则另一条链上的A的比例是()
A.9%
B.27%
C.28%
D.46%