ОК("I'd like to book a table for six this evening" "Can do. What name, please?" – "Я бы хотел заказать на вечер столик для шестерых" – "Будет сделано. Фамилия, пожалуйста" VLZ_58)
совершенно не уметь что-либо делать(if you say that someone can't do something to save their life, you mean that they are extremely bad at that thing: I can't draw to save my life. Bullfinch)
не могу(No can do, I'm afraid – I need the boss's signature for that. • "Can you give me a ride to work tomorrow?" "Sorry – no can do. My car is in the shop."4uzhoj)