A2
used to show that each person in a group of two or more people does something to the others
Dictionary examples:
The twins kept tickling each other during the boring class. (0.0)
The friends kept copying each other's homework, getting caught every time. (0.0)
The students kept correcting each other's English mistakes. (0.0)
They're always wearing each other's clothes. (16.7)
They kept looking at each other and smiling. (17.6)
Why are you always arguing with each other? (20.6)