もしないで

1. 1Criticizes someone for acting without even taking a minimal, expected step first.Ex. 1
2. 2Describes one's own past action with regret at having skipped an obvious step.Ex. 2
3. 3Expresses surprise or admiration that a result was achieved without even the usual preparatory step (e.g. 地図を見もしないで目的地に着いた).

Neutral in register and used in both speech and writing. It often appears in scolding, complaints, or self-reproach, where the main clause may be a prohibition or end in てしまう. It can also describe an impressive or surprising result. Plain ないで and ずに simply state that an action was not done, whereas も adds an emphatic "not even" nuance.

• ないでN3「ないで」 attaches to the ない-form and plainly means 'without doing…'; it also has a 'doing B without doing A' use and a sentence-final request use. 「もしないで」 adds the emphasis 'not even doing this', so swapping in 「ないで」 only loses that emphasis—the sentence can still carry a blaming tone.
• ことなしにN1「ことなしに」 attaches to the dictionary form and is written-style. It usually pairs with a negative or rhetorical question in the following clause to stress that the first item is indispensable, and it can also simply mean 'doing B without doing A'. It lacks the blaming tone of 「もしないで」 and the two are generally not interchangeable.
• ずにN3「ずに」 objectively means 'doing B without doing A' or 'doing B instead of A', with no blaming nuance; it attaches to the ない-form (e.g. 「読まずに」) and leans written. When emphasizing that even the bare minimum is not done, with displeasure, use 「もしないで」 (written-style 「もせずに」).
• ことなくN2「ことなく」 attaches to the verb dictionary form and is formal written-style, used in neutral narration. It emphasizes that something that could have happened never does, often co-occurring with 「一度も」. 「もしないで」 carries a tone of blame or surprise, so the two are generally not interchangeable.
• (で)すらN1「(で)すら」 is a particle highlighting an extreme example, attaching mainly to nouns, and it can be used in affirmative sentences (e.g. 「子供ですら分かる」). Its only similarity to 「もしないで」 is in negative uses like 「見すらしない」, and 「すら」 is more written and stiffer.
• さえN3「さえ」 is a particle that attaches to nouns, verbs, and more, meaning 'even…' with a neutral tone. It is similar to 「もしないで」 only in the sense 'not even doing… (before/without)…': 「読みさえしないで」 is close in nuance to 「読みもしないで」 and mostly interchangeable.

Plain ないで and ずに just mean "without doing," while もしないで adds that not even a basic step was taken; ことなく and ことなしに are more formal, written expressions without this "not even" emphasis. さえ and (で)すら are general "even" particles that attach to many kinds of elements, whereas もしないで is a set pattern for actions that were not done.