基因在某一染色体上的排列叫____。确定某一基因在染色体上的位置叫做____。
参考答案:遗传图,基因定位
The river smells terrible. People_______ dirty things into it .
A.must stop to throw
B.must stop from throwing
C.must be stopped to throw
D.must be stopped from throwing
简述拉威尔及其创作特征?