Idioms: on moral grounds -- on our last legs

Idiom	Meaning	Example
on moral grounds	based on what is right and wrong	We refuse to accept money from drug dealers - on moral grounds.
on my back	criticizing me, on my case, ride me	The coach is on my back about missing the game last week.
on my best behavior	being polite to everyone, behaving in an appropriate manner	I promised my mother that I will be on my best behavior at her wedding. I will be a very good boy.
on my case	looking for my mistakes, criticizing me	The coach is on my case again, yelling at me to play harder.
on my deathbed	nearly dead, very ill, at death's door	I was so sick, I thought I was on my deathbed.
on my good side	to become my friend, in my good books	He says nice things to me, hoping to get on my good side.
on my plate	on my schedule, on my list of duties or tasks	I have too much on my plate right now. I'm too busy.
on my way	continue my journey, departing	Before I leave, I'd like a cup of coffee. Then I'll be on my way.
on my word	(See upon my word)
on our last legs	nearly dead or bankrupt, nearly done for	Financially, we were on our last legs. We couldn't get a loan.