—I'm glad to hear that,But I think you still ______
A:have a long way to go
B:have fun
C:have a rest
D:have a good time
I still remember my happy childhood when my mother ____ me to Disneyland at weekends.
下列实验不属于对应基础实验内容的是( )
果蝇的体色由常染色体上一对等位基因控制,基因型BB、Bb为灰身,bb为黑身.若人为地组成一个群体,其中60%为BB的个体,20%为bb的个体,群体随机交配,其子代中Bb的比例是( )