- плохо будет
- • ХУДО <ПЛОХО> БУДЕТ (кому) coll[VP; impers; these forms only; usu. a clause in a compound sent; preceded by one or more clauses expressing prohibition, warning etc; often after а то, не то, иначе etc]=====⇒ (if s.o. disobeys an order, fails to do what he should do etc) there will be trouble (for him and/ or another or others):- X will be in hot water;- X will have the devil to pay;- X will come to a bad end;- [when the situation is already bad] things will only get worse.♦ "Раз подъехал к нему и говорю шутейно [substand = шутливо]: "Пора бы привалом стать, ваше благородие - товарищ Мелехов!" Ворохнул [substand, here = сверкнул] он на меня глазами, говорит: "Ты мне эти шутки брось, а то плохо будет" (Шолохов 5). "One day I rides up to him and says joking like, Time to call a halt, Your Honour-Comrade Melekhov!' And you should have seen his eyes flash! 'Just you drop those jokes of yours, or you'll come to a bad end,' he says" (5a).
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.