To take something with a pinch of salt - to listen to a story or an explanation with considerable doubt. Example - "You must take everything she says with a pinch of salt. She doesn't always tell the truth"
To put your finger on something - to discover the exact reason why a situation is the way it is, especially when something is wrong. Example - "There's something odd about him but I can't quite put my finger on it"
To take stock - to think carefully about a situation or event and form an opinion about it so that you can decide what to do. Example - "After two years spent teaching overseas, she returned home for a month to take stock of her life"
To grate one somebody's nerves - to annoy someone a lot, especially by doing something again and again. Example - "The telephone hasn't stopped ringing all morning and it was starting to grate on my nerves"
Struck off - if someone with a responsible job such as a doctor or a lawyer is struck off, they are officially not allowed to continue in that work because of having done something seriously wrong. Example - "A solicitor who insulted two officials from the Law Society was struck off for abusive behaviour"