eg.  In order to catch the first train, he set off early.

He set off early so as to catch the first train.

In order to keep fit, one needs to do plenty of exercise.

We must hurry up so as not to be late for the meeting.

2.由in order that, so that（为了）引导的目的状语从句中

的谓语部分需用情态动词may/might; can/could;

shall/should; will/ would。 

3.in　case引导的目的状语从句中的谓语部分常用一般时，

 不用将来时。

　　4． 由in order that和in case引导的目的状语从句可位于主句

前，也可位于主句后,而so that引导的从句只可位于主句后。

　　eg. He sent the letter by air mail in order that（或so that）it might reach them in time.

　　    这封信他航空寄去，以便他们能及时收到。

       Let’s take the front seats in order that/ so that we may see more clearly.

       In order that you can be heard by all you must speak louder.

      Better take more clothes in case the weather is cold.

He wrote the name down for fear that he would not forget it.

The teacher spoke slowly so that I should get it.

让步状语(Adverbial of concession)

1.  despite和in spite of为介词，引导让步状语时后接名词或名词性短语。

eg.   Despite the pressure, I love my job very much.

        In spite of the cost, he sent his son to the best school.

        He keeps on working night and day despite/ in spite of his poor health.

2.  although, though, as, even though, even if引导让步状语从句，不能和but连用。

eg.  

He didn't stop working though/although he was ill.

Although I tried very hard, I failed to persuade him.

Even though the task is difficult, they managed to accomplish it on time.

Good as he is, he will never be top of his class.

Hard as/though he works, he makes little progress.

Despite/ in spite of…… 和although/though/even though + cl.之间的转换。