[sent; these forms only; used as sent adv (parenth); fixed WO]
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⇒ used when telling one's hearer(s) about sth. unusual, astonishing, outrageous:
- I <I'll> tell you;
- I've got to tell you;
- let me tell you.
♦ "Ну и в историйку я недавно влип, доложу тебе", - начал он... (Искандер 2). "Well, I'll tell you, I really fell into something once not so long ago," he began... (2a).
♦ Был я, доложу я вам, слаб, капризен и прозрачен - прозрачен, как хрустальное яйцо (Набоков 1). I was, let me tell you, weak, capricious and transparent-as transparent as a cut-glass egg (1a).
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.