grammar → 根本
TSUMUGU · TBCL 4 (est.) · 語法
根本 grammar point · tier 1 · emphatic adverb 根本 (at root / not in the slightest)
· gēnběn
Adverb before the verb meaning at root; paired with a negator (沒/不) it denies the action all the way down — not at all, not in the slightest.

字源 FORM what the parts do

Both halves write the same root. 根 is the root under a tree (木), 艮 lending only the sound. 本 is a tree (木) with one stroke cut low on the trunk, marking that same root. Stacked, they point past the surface to where a thing actually stands.

故事 STORY a scene to remember it by

A hand digs down past the trunk to the root, and there is nothing there to hold.
字源記憶法
框 · Frame
[subj] 根本 [不/沒 + verb phrase]
觸 · Trigger
You want to deny something at its source: no basis for it at all, not a degree short.
序 · The move
1Put 根本 in front of the verb, before the negator.Does it sit as 根本不 / 根本沒, not after the verb?
2Keep the negator: 根本 leans on 不 or 沒 to carry the denial.Is there a 不/沒 for 根本 to reach down to? Bare 根本 + verb reads as affirmative emphasis, a different move.
3Read it back as not at all / no basis for it.Is the claim a total denial, not a partial one? If it is only somewhat, 不太 fits, not 根本.
例 · Examples
1他每天工作都很忙,根本at root; not at all沒時間have no timewith孩子們相處get along together; spend time with
He is busy with work every day and has no time at all to spend with the children.
界 · Boundary
連…都…
連…都… includes the hardest case to imply all the rest; 根本 strikes at the root to deny the whole thing. 連飯都沒吃 = didn't even eat (the basic case); 根本沒吃 = didn't eat at all (no basis for it).
本來
本來 looks back to how things originally stood (originally, at first); 根本 measures depth now (at root, fundamentally). Same 本, different reach.
他根本不忙一點 ✗ → 他根本不忙 ✓
他沒時間根本 ✗ → 他根本沒時間 ✓
我根本有點累 ✗ → 我有點累 ✓ (use 根本 for total denial, not a partial degree)
English 'basically' and Chinese 根本 share the 'root' image but split: 'basically' softens (more or less, roughly), while 根本 with a negator hardens into not at all. Mapping 'basically' onto 根本 reverses the force.