May / Might as well :  This particular expression is used for making suggestions.  This expression suggests a different course of action would be preferable and this frequently occurs in everyday conversation.  This is used mainly on informal occasions.  ‘ Might as well ‘ is more common than ‘ May as well ‘.

A :  Here comes the bus.  We might as well take it.

B:  Yes, we might as well.

A:  How slow this bus is ! We might as well walk.

B:  We might as well have gone on walking.

•   They don’t seem to come in time and it is pointless to wait for them.  We might as well get a taxi and go home before it gets dark.

Note : We can make ‘ May as well ‘ and  ‘Might as well ‘ stronger by using ‘Just ‘ after May or Might.

• We don’t  know anyone here and the matter they want to discuss doesn’t concern us. We might just as well go somewhere else.
• It’s a choice between a job and an admission in a college.  You may just as well take the job .  At least you’ll earn some money.