You can limit answers to a specified number of characters or require a certain number of characters by using the Length response validation.
Similarly you can enforce a minimum character limit for any paragraph question.
You can write a regular expression to impose a word limit on the answer. The regex can be used to enforce a max or a min word count. For example, the below regex will restrict the answer to 300 words. ^\W*(\w+(\W+|$)){1,300}$
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