Take a look at these two sentences:
If you do not submit all documents by 31 January, your application will not be considered.
You must submit all documents by 31 January to be considered.
Which did you understand faster? The first sentence uses the word "not", so it's cast as a negative. The second is constructed as a positive.
Negative constructions make the reader work a bit harder because they have to "first imagine the positive alternative, and then mentally cancel it out" (Martin Cutts, Oxford Guide to Plain English).
So when you can, try to cast the sentence in the positive.
On the blog: Learn more how to recast negatives into positives
(But you use “do not” and “must not" when you're prohibiting something.)
Check out some more easy tips on writing clearly for diverse audiences. 👓
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