Purpose with to, in order to and so as to
Use to , so as to, and in order to to express purpose in the affirmative form.
Examples:
- He is looking for a part time job to save some pocket money.
Purpose with for
Purpose can be also expressed by using for. For may be followed by either a noun or a verb + ing.
Examples:
- I stopped there for a chat.
- This mop is for cleaning the floor.