何以……

何以…… means "how; why; by what means" and follows the frame 何以 A. Use it when the sentence needs to ask for the reason or means in a formal way. Pay attention to register: many patterns in this group are formal, evaluative, or rhetorical, so they are stronger than everyday words. Do not choose a pattern only because the translation looks close; check whether the sentence is evaluation, sufficiency, inevitability, suggestion, or rhetorical affirmation/denial. Common mistakes include dropping fixed characters such as 于, 是, 不, 能, 非, confusing 为什么, 怎么, 凭什么, or using a rhetorical pattern in a neutral statement.