1. tobe hard done-by
e.g. She feels hard done-by because she's been looking after the kids all week while her husband hass been out every night.
2. tobe miles away
e.g. I was miles away thinking of my financial affairs while Sara was speaking to me.
3. like water off a duck's back
e.g. Her mother told her off for being so cheeky, but it was like water off a duck's back
4. sth takes some doing
e.g. Your computer is on the blink and I can fix it up for you, but it takes some doing if you wish.
5. tobe in with a chance of...
e.g. I was in with a chance of having a good family and they've always been for me a leg to stand on.