二倍体
参考答案:
含有两套染色体,分别来自父本和母本
----Where is Jack?
----On the playground. He _______ football with his classmates.
A.play
B.played
C.is playing
D.was playing
民主立法就是积极探索公众有序参与立法的途径与形式,广泛征求基层群众的意见和建议,不必征求专家的建议和意见。