The paragraph is followed by an incomplete phrase or sentence which summarizes the main idea of the paragraph. Choose the missing words of the phrase or sentence.

When you wear cap and gown at ceremony of conferring degrees or diplomas, you will be following a custom that is many centuries old. The use of caps and gowns in college and universities goes back to medieval times. Nearly all gowns are made of black cloth. Some doctoral gowns use other colors, but the vast majorities are black.
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