根本【gēnběn】

根本 before 不 or 没 rules something out completely: not at all, not in the slightest. It often contradicts what someone has just assumed.

就 between them makes it blunter still.

Where it goes

根本 comes before the negative, the same as 一点儿也 does, not after it.

• × 我不根本知道 → 我根本不知道

In positive sentences

Without a negative, 根本 means "fundamentally" or "simply", and 就是 often follows: what was said is wrong from the ground up.

根本 is also "the root" or "basic": 根本问题 is the fundamental problem, and 从根本上 is "at the root".