A run in – an argument “I’ve had another run-in with the neighbours”
To be on the run– to be running from the police “Did you hear about the serial killer on the run in London?”
To run amok – to act in a wild and crazy way “Don’t leave the kids alone, they’ll run amok!”
In the long run – in the distant future “If she studies now, she’ll be better off in the long run”.
To run out of steam – to lose energy and interest “By 6 o’clock I’d run out of steam, it was a long day.”