Not all arguments are deductive arguments. Deductive arguments may be recognized by their characteristic forms. The form of an argument can be recognized by identifying keywords. Because deductive arguments constitute a particular sort of reasoning, they entail the use of a particular set of words. In particular, there are three types of key words to watch for.
1. Mathematical keywords: plus, minus, equals
2. Categorical keywords: is, all, some, no, every, any, only
3. Propositional keywords: both...and, either, ... or, if .. then, unless
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