Translation guide
Used to add a stronger or more obvious point to an already stated one, meaning 'not to mention' or 'let alone'. In Japanese, this is expressed with particles and phrases that emphasize the obviousness of the second item.
Adding a stronger or more obvious point to emphasize the extent of something
A common pattern meaning 'not only A, but also B' or 'A, to say nothing of B'. A is the more obvious or expected, B is the additional point.
He can speak French, to say nothing of English.
This restaurant has great service, to say nothing of the taste.
Similar to はもちろん, but slightly more formal. Used in written or formal speech.
Used to say 'far from A, even B'. Emphasizes that B is even more true or extreme. Often used when A is expected but not even achieved, and B is even less likely.
どころか can also mean 'on the contrary', so context is important. It often implies the first item is not true, unlike はもちろん.
A formal, often written pattern meaning 'let alone A, even B'. Used to emphasize that B is also true or not true, with A being the more obvious case.
はもちろん is the most common and neutral. はもとより is formal/written. はおろか is formal and often used in negative sentences to emphasize that even a lesser thing is not true. どころか is different: it often negates the first item and adds a stronger contrasting point.
He can't read hiragana, to say nothing of kanji.
He can't afford a car, to say nothing of a house.
This issue is attracting international attention, to say nothing of domestic.
Far from apologizing, he got angry — to say nothing of apologizing.
He has never traveled domestically, to say nothing of overseas.
彼は漢字はおろか、ひらがなも読めない。
He can't read hiragana, let alone kanji.
Do not translate 'to say nothing of' literally as 何も言わない (say nothing). It is an idiomatic phrase meaning 'not to mention' or 'let alone'.
She is good at math, to say nothing of science.