1 (spoil) [+activity, event, plans] dar al traste con; echar a perder it's the little things that can foul up your plans los detalles son los que pueden dar al traste con echar a perder los planes de uno;or
I'll stay here until the VIPs come just in case these two characters foul things up it is, after all, Mr Major who has fouled things up so spectacularly in this government Critics of DNA fingerprinting say there are serious risks that laboratories may foul up these tests we're in the middle of a production. Millions of dollars are at stake. My concern is getting the thing finished. Any little hiccup could foul it up
2 (make a mess of) he has fouled up his exams los exámenes le han ido mal; ha metido la pata en los exámenes; (informal)
she has fouled up his career
