one by one

"During the reaction on the catalyst surface, methane will lose its hydrogen atoms one by one until only its one carbon atom is left," Zhang said.

The family hung on in their house as long as they could, but with explosions all around, shops closed and roads cut off one by one, they finally bowed to the inevitable.

Eventually, Danny breaks down the door of the next building along and, one by one, he pulls the children to safety.

But, one by one, procedural and legal challenges assured that those cases against Trump would not be tried until after the election.

Over martinis at Figaro, my friends pull out their lipsticks and glosses one by one.