Section_ⅣGrammar_&_Writing

　　语法图解

　　探究发现

　　①Both of these medicines have proved beneficial to mankind since they were invented.

　　②Within a short time, aspirin became the best­selling medicine in the world for pain relief.

　　③He noted that a dish in which he was trying to grow bacteria for an experiment looked abnormal.

　　④Another drug that has helped increase the standard of people's health is penicillin.

　　⑤Many people has fallen ill because of the cold weather.

　　⑥It turned out that my judgement was right.

　　⑦It seems as if he has lost interest in his new job again.

　　⑧Please keep silent at the meeting unless you're allowed to talk.

　　[我的发现]

　　(1)以上各句中的黑体词均为连系动词。连系动词本身有一定词义，但是不能单独作谓语。其中④句中的be是最常用的连系动词。

　　(2)③句中的黑体词为"感觉感知"类连系动词。

　　(3)⑧句中的keep为"状态持续"类连系动词，而①句、⑥句和⑦句中的黑体词为"主观判断"类连系动词。

　　(4)②句和⑤句中的黑体词为"状态变化"类连系动词。

一、系动词的分类