Question

请问这道题选什么？考的是非谓语动词吗？

If ________ in a hot place, these flowers will soon begin to die and fall.被动
A. be put B. to put C. put D. putting

Answer 1

这道题其实考的是如何将条件从句变成if短语，if短语中涉及的实质内容是非谓语动词。
本题前半部如果改成if从句，应该是if they are put in a hot place.英语语法规则规定：对于谓语动词是被动语态的if从句，改成if短语时，除了要去掉主语外，还要使用动词的过去分词。于是，将上述if从句变成if短语时，要将they去掉，同时把are put改成动词put的过去分词形式put，也就成了if put in a hot place.
需要注意的是：如果if从句的谓语动词使用的是主动语态，则改成if短语时除了去掉主语外，需要用动词的相应的现在分词形式。例如：
①If he takes a bus, the teacher would get there on time=If taking a bus, the teacher would….
②If he had taken a bus, the teacher would have got there on time.=If having taken a bus, the teacher would….