not to mention... 更不用說……
= not to speak of... +「名詞或動名詞/介係詞片語」
= to say nothing of...
Judy can speak English, not to mention Japanese.
Judy can speak English, not to speak of Japanese.
Judy can speak Englosh, to say nothing of Japanese.
Amy likes to walk in the morning , not to mention at night .
He doesn’t love himself, to say nothing of others.
let alone... 更不用說……
= much less...
He can’t afford a car, let alone a cellphone.
肯定意味的句子 + still more / much more，意指「而且還…」。
否定意味的句子 + still less / much less，意指「更別提；更不用說」。
let alone :還有一層的意思，當（不管、不打擾、不干涉、不理）
let + 受詞 +alone= leave +受詞 + alone
(A) Let her alone when she is not happy.
(B) You may stay with me as long as you let me alone.
not much of 算不上，稱不上
He is not much of a hero. 他並不是一位英雄。
Not much 不多，沒什麼，不多，很少