he fought like a lion ... A simile is a sentence that compares one thing to another ... So it has to have both things that are being referred to, like "he" and "lion", where the way the person is fighting can be compared to the fighting of a lion. But you need to remember that a simile has the word "like" or "as" ... Otherwise it cannot be a simile, it would be a metaphor ... I hope this was helpful ...
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