〜はおろか
let alone, not to mention
Noun + はおろか、Noun + も / さえ / すら / まで
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はおろか says that the obvious case is out of the question, and even a lesser one fails: 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".
The first noun is the bigger or harder thing, and the second, with も, さえ, すら or まで, is the smaller, more basic thing. It's usually negative, and often expresses surprise or criticism. With a positive, it can mean "not to mention": 貯金はおろか、借金まである, "far from having savings, I've even got debts".
It's close to どころか (N2). Compare はもちろん (N2), "of course", which lists good things. はおろか is almost always about something bad.
Note the order: まして puts the harder case second, but はおろか puts it first.
Examples
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.
旅行はおろか、近所に出かける時間もない。
Forget travelling, I don't even have time to pop out locally.
貯金はおろか、借金まである。
Far from having savings, I've even got debts.
彼は謝罪はおろか、説明すらしなかった。
He didn't even explain, let alone apologise.
車はおろか、自転車も持っていない。
I don't even own a bike, let alone a car.