在家禽和家畜培育过程中，通过杂交育种和人工选择作用，可以培育出适应性强的乳用、肉

He asked me, “Did you see my sister last night?”

----He asked me __________

A．if I had seen his sister the night before.

B．whether I had seen your sister the night before.

C．did I have seen his sister the night before.

D．that I saw his sister the night before.

下列哪一项不是水平传播（）

A.空气传播

B.经水传播

C.娩出前从母亲到后代之间的传播

D.经食物传播

E.经媒介节肢动物传播

即使到了冬天，小王也做到了每天早起。

三类防雷建筑直击雷的措施中，专设引下线不应少于2根，并沿建筑物四周均匀对称分布，其间距沿周长计算不应大于（）mm。

A.12

B.18

C.25

D.30

按照剪切温度的不同，剪切可分为（）。

A.热剪和冷剪

B.平行剪和飞剪