You can borrow some money if you really want to.
If you want to look smart, you should cut your hair.
To save some money, I think he ought to eat at home more often.
We have to put the lights out by midnight every night.
The house is so dirty - I really must clean it.
Staff wishing to smoke may use the garden.
To express obligation
To express obligation
To give advice
To give advice
To give permission
To give permission