更別說…了grammar point · tier 2 · 更別說…了 (let alone, to say nothing of)
Grants a mild case to make an extreme case follow without stating it: X already holds at the weak end, so it holds all the more at the named harder end.
Grants a mild case to make an extreme case follow without stating it
框 · Frame
[mild case stated] ，更別說 [harder case] 了。
觸 · Trigger
You have conceded a weak case; the stronger case follows so plainly you wave it off rather than argue it.
序 · The move
1State the mild case plainly first — the low rung that already shows the quality.Is the first clause the EASIER end of the scale, the one harder to expect the quality at?
2Put 更別說 in front of the harder case, the one where the quality is even more certain.Does the second case out-rank the first on the same scale (colder, harder, more obvious)?
3Close with 了.Run it backwards: if the harder case sat first, the line breaks — that means the rungs are in the right order.
例 · Examples
1山上的天氣非常寒冷，白天daytime — the milder case, conceded first也才五度only five degrees even (then) — the quality already shown at the weak end，更別說let alone / to say nothing of — even more so, no need to say夜晚night — the harder case, colder still了closes the case as settled。
The weather up the mountain is bitterly cold — only five degrees even by day, let alone at night.
連…都… stresses one surprising case inside a single clause (even THIS). 更別說…了 spans two cases across a scale: grant the weak one, wave off the strong one as obvious.
越…越… ties two things rising together in proportion (the more X, the more Y). 更別說…了 ranks two cases on one scale and infers the harder from the milder — no second variable moves.
✗ 更別說夜晚了，白天也才五度。 → ✓ 白天也才五度，更別說夜晚了。 (mild case first, then 更別說 the harder case)
✗ 他連中文都不會說，更別說英文了，可是英文比中文難。 → ✓ 他連基礎的中文都說不好，更別說流利的英文了。 (the 更別說 case must out-rank, not under-rank, the first)
✗ 白天五度，更別說夜晚。 → ✓ 白天也才五度，更別說夜晚了。 (close with 了)
English speakers reach for 'let alone' and stop at 更別說, dropping 了. The 了 is not optional here — it seals the conceded case.