At every turn
Everywhere that one looks. When we visited Rome, there was a group of tourists at every turn.
At ease
To be relaxed and comfortable. The players felt at ease after the coach talked to them.
At death’s door
To be near death. The young woman was at death's door after the accident.
At cross-purposes
To have opposite ways of doing something, to have opposing goals. The two men are at cross purposes. They cannot agree about anything.
At best
Under the most favorable circumstances. The doctors said that the man had ten months at best to live.
At bay
At a distance. We tried to keep the dog at bay when we entered the building.
At any rate
Anyways. At any rate, I am not going to a movie tonight.
At all costs
Regardless of the cost or difficulty, no matter what. The company wants to protect their product design at all costs.
At a stretch
Continuously. My friend sometimes works for three weeks at a stretch.
At a standstill
In a situation where no progress can be made, at an impasse. The traffic on the road was at a standstill because of the accident.