thing /ˈθɪŋ/ noun
9 [singular] : a reason for something
▪ I can't stand being around him. For one thing, he smokes. For another, he's rude.▪ OK, here's the thing: I don't have enough money to go to college.▪ I'm sorry I didn't call you. The thing is, I've been really busy with work and school.▪ The thing is that I haven't had time to call you.
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for one thing
one reason is For one thing, sun screens block more of the sun's damaging rays, so they are much more effective. I like smaller companies - they're more personal for one thing.
