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should (be); bound (to be); expected (to be); must (be)
nock (of a bow)
nock (of an arrow)
nock-shaped grip (between thumb and forefinger)
wooden frame on the tip of the mast of a Japanese ship that prevents the hawser from falling out
彼はもうすぐ来るはずです。
He should come soon.
もう着いているはずですよ。
They should have already arrived.
できるはずなのにできません。
I should be able to do it but I can't.