done: Avoid using the past participle of verbs instead of the imperfect. Do not say, “You done it,” or “you seen it,” when you mean “you did it,” or “you saw it.” Nor use the past tense for the perfect participle, as in, “If you had came” when you mean “If you had come.”
don’t is a contraction of do not, and in this sense is permissible; but as signifying does not, the proper contraction for which is doesn’t, its use is inaccurate. In writing, the uncontracted forms are much to be preferred, though in conventional speech the abbreviations are accepted.
don’t believe, don’t think: “I don’t believe I’ll go”; “I don’t think it will rain”; solecisms now in almost universal use. Say, rather, “I believe I will not go”; “I think it will not rain.”
don’t make no error. See [ERROR].
dopey: A vulgar substitute for “sleepy; dull; thick-headed.”
dose, doze: Discriminate carefully between these words. That which a physician prescribes is a dose; that which a sleepy patient may fall into is a doze.
do tell! An exclamation of surprise the equivalent of which is “Is it possible!”—an inane provincialism to be avoided.
doubt. See [WHETHER].
doubt but that: In this phrase but is superfluous as it does not add anything to the sense.