(If it is something like an instruction then) I think 'Think positively' can be good. This is a quotation from OALD dictionary: Thinking positively is one way of dealing with stress. g.
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I just guess that it could be good with 'positive' if it was a linking verb (e.g. 'feel', 'sound', etc.). As far as I know 'think' is not that type. But I'm not sure.
Thinking positively is one way of dealing with stress.
Rommel Which is grammatically correct: "Think positive" or "Think positively"?Think positively is the correct form, but the popular expression is always Think positive, formed by analogy with Be positive (Have a positive attitude).
Hole One a New SeeI just guess that it could be good with 'positive' if it was a linking verbGood guess.