どうか, どうにか, どうかして - differences?

Question

I was just wondering what the essential differences are between these and how I would use them in everyday speech. Thank you.

Answer 1

どうか has different meanings contextually depending on what comes before or after. when it is at the beginning of a phrase, however, it is quite similar to どうにか. nuance wise, I would roughly translate it as "please, could you somehow" and is used when you are desperately asking something of someone. An example would be どうか助けてください。meaning "Please help" (with a desperate nuance). However, it really depends on the sentence, because どうか translates to "how about ____?" when it appears at the end of a sentence, functioning as a polite suggestion.

どうにか is used slightly different, in situations when you are against the odds. For example, どうにかして彼を見つけた。translates to "I somehow (against the odds) was able to find him". While both どうか and どうにか can be interpreted as "somehow", どうにか implies that it is/was against the odds, and doesn't mean "please".

どうかして is usually followed by る (いる) and implies someone or something is not right/crazy, setting it apart from the former two phrases. 彼の頭がどうかしている is basically saying "he's crazy".