英語クイズ　Preposition, conjunction, verb, infinitive and idiom

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Tiny and slender     it is, a metal bar hidden     the frame and tongue of the buckle works     the core     it all. It not only connects the buckle       the belt but also supports the tongue as it moves in and          the holes, fixing the belt         our waists and releasing it day        day.       the outside, it looks like the tongue and frame     all the work, but it is actually the bar that lets them do their job. They can’t work          it. That’s why it is the         hero of the belt.