demonstrate，illustrate
demonstrate 证明，论证，以科学严谨的态度，通过推理、辩论或提供证据来证明事物的正谬。illustrate 指用实物、图片等进行说明，illustrate后常用介词by，with。
A．The lecturer ＿＿＿＿ his point with a diagram ont heblackboard．
B．To ＿＿＿＿ his arguments，he showed us a lot of facts．
C．These figures clearly ＿＿＿ the size of the economic problem facing the country．
Answers：A.illustrated B.demonstrate C.demonstrate
