一、现在分词和过去分词作状语的区别
主要区别在于：现在分词与修饰的主语为主动关系，过去分词与修饰的主语是被动的关系。
（1）现在分词作状语时，现在分词的动作就是句子主语的动作。
He went out shutting the door behind him.
Not knowing what to do, he went to his parents for help.
（2）过去分词作状语时，过去分词所表示的动作和句子的主语承受的动作，它们之间的关系是被动关系。
Given more attention, the trees could have grown better.
Faced with difficulties, we must try to overcome them.
二、动词不定式和分词做状语的区别
（1）分词常常表示为伴随，而动词不定式表示目的。
They stood by the roadside taking about the plan. //分词表示伴随
They stood by the roadside to talk about the plan. //不定式表示目的
（2）分词作状语放在句子开头，除表示原因之外有时表示时间或条件。动词不定式作状语时，除了表示目的以外，还表示结果或原因。
Reading attentively, he forgot the time for lunch. //分词表示原因
Reading carefully, he found something he had not known before. //分词表示时间
Reading carefully, you'll learn something new. //分词表示条件
His family was too poor to support him. //不定式表结果
The boy is not tall enough to reach the book. //不定式表示结果
We are glad to hear the news. //不定式表示原因\
三、下面句型是不定式做状语时候应该注意的：
（1）not/ never too...to/ too...not to, but/ only too..to, too ready/eager/apt/inclined to表示肯定意义。
（2）做结果状语的不定式只能出现在句子的末尾，常见的不定式动词有：find,hear,see,be told,form,give,make,produce等。
（3）不定式作状语时，其逻辑主语一般为句子的主语，否则用for引导主语。
