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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
彼はもう着いたはずです。
He should have arrived by now.
この本は面白いはずだった。
This book should be interesting.
彼女が知っているはずがない。
There's no way she knows.