Can't afford it, can't stand it: 不起 / 不了
Some potential complements are so common they've become words of their own. V不起 means "can't afford (to)": 买不起 "can't afford to buy", 吃不起 "can't afford to eat (there)". V不了 (liǎo!) means "physically can't manage": 受不了 "can't stand it", 吃不了 "can't finish (the food)".
Add the time-critical pair 来得及/来不及 ("there's still time / too late") and you have the survival kit. One booby trap: 看不起 doesn't mean "can't see" — it means "to look down on." "Can't see" is 看不见.
Examples
Common mistakes
Related grammar points
Practice this pattern in graded stories like Can't Take It Anymore (Part 1), The Late Train to the Sea (Part 2), The Picnic That Almost Wasn't (Part 1) inside the Literate Chinese app.
