— Whose model plane is it?
— It's Jack's. He made it by _______.
A:he
B:Him
C:himself
调查显示,上海市居民消费呈现下图所示特点。对此认识正确的是( )
声音是由物体的____产生的,当神八和天宫1号在太空成功对接时,我们看到了强烈的碰撞,却丝毫没听到碰撞声,原因是____.