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surely; undoubtedly; almost certainly; most likely (e.g. 90 percent)
sternly; severely
having no slack; rigid; stiff; tight
天気予報によると、きっと明日は晴れます。
It will surely be sunny tomorrow.
きっと成功するはずです。
You will certainly succeed.
きっと来てくれると信じています。
I believe they will surely come.