All those are valid usages, but I think you didn't mean what you said in the last sentence - it effectively means "the enemy was difficult, but that didn't stop them from giving up" which doesn't sound like what you were going for.
I think you meant either "didn't cause them to back down" or "didn't stop them from fighting on" or something similar.
Mar 21, 17 · +1 · Like · Report
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