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