1. There was an air of intensity in the boardroom, you could tell they were in a stormy meeting.
* when one uses this it usually involves a lot of angry argument or criticism.
2. This morning I was told I was skating on thin ice as it had been my third time arriving to work late this week.
* If you say that someone is on thin ice or is skating on thin ice, you mean that they are doing something risky that may have serious or unpleasant consequences.
3. John is amazing as a salesperson, he could sell everything under sun.
* This means someone could convince you about everything one can reasonably imagine; many different things, often to the point of excess or redundancy.