They fell one after another.
They fell in love with each other at first sight.
They were criticizing each other.
They roared the speaker down.
They held each other tight.
They hugged each other.
They embraced each other.
They clicked with each other.
Their opposition broke down.
They are all dead.
They stood up simultaneously.
They started out in opposite directions.
They broke down part of the wall.
Those were canceled out.
Those were counterbalanced.
They fell out with each other over trifles.
They faced each other.