— Though Mike is _______ boy, he can say many words.
— How clever!
A:an-one-year-old
B:a one-year-old
C:an one-year old
D:a one-year old
质粒是基因工程中最常用的载体,不属于质粒被选为基因运载体的理由是 ( )
一字组多词
隐____ ____ 计____ ____
旺____ ____ 墨____ ____