两道语法题

0308
11． In jazz music, a riff is a simple melodic figure, _________ and repeated several times.
(A) usually one or two measures lasted
(B) lasted one measure or two usually
(C) is lasting one or two measures usually
(D) usually lasting one or two measures
我选了B，答案是D，我觉得and前后要并列啊

31.   Some ways in which lizards different from snake are in having ear openings, moveable yelids, and less flexible jaws.

我知道要把different改成differ,但是我觉得C的in 好象是多余的？为什么后面having 前有个in呢

11、B选项中usually的位置不对；D选项从意思上来看似乎没问题啊，last是主动的,后面的repeat是被动的。

31、我也不知道为什么having前有个in，不过既然确定different是错的，选它就行了。