16. provide necessary impetus for … 给与…动力
e.g. It is almost always a key individual who provide the necessary
imputes for what otherwise might be a group effort, as discussed below.
17. favor v.赐予；给与
e.g. He was favored with great intelligence. || adduce facts to favor one’s
contention.
18. paradigm n.样式；典范；范例
e.g. educational paradigms
19. obscure v.使阴暗；使朦胧
e.g. Generally speaking, then, undue attention to the efforts and
contributions of various groups tends to obscure the cause and effect
relationship with which the study of history is chiefly concerned.
20. take steps to … 采取措施…
e.g.take step to help alleviate social problems
