I've got to decide by next week.
I'm going to have to do something about it.
I ought to do some volunteer work.
You don't have to spend time on this.
WHAT'S PREFERABLE
You'd better do something quickly.
I'd better not add anything to my schedule.
WHAT'S NECESSARY
You ought to let them do the talking.
I'd rather (not) stay in my current job.
You might want to take a colleague with you.
WHAT'S ADVISABLE
