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 English, to say nothing of Japanese.
Amy likes to walk in the morning, not to mention at night .(Amy喜歡早上散步，更不用說在夜晚)
He doesn’t love himself, to say nothing of others.(他不愛他自己，更不用說其他人)
= much less…(用於否定句中)
He can’t afford a pen, let alone a cellphone.(她無法負擔一枝筆，更不用說一支手機。)
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」。
He can’t speak English well, much less Japanese. (他連英文都說不好，更別說日文了。)
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.(只要你不打擾我，你就可以留下)
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