He said he had created a new musical form -- an opera based on popular culture.

VOA: special.2009.02.15

There are definitions based on form, circularity, symmetry, economy of form, lack of economy of form, and repetition.

有些定义是基于形式，循环，对称，形式的精简与否，重复。

耶鲁公开课 - 文学理论导论课程节选

It's based on the ancient form of Japanese poetry, which is something that I had never tried myself.

这些诗是根据日本古代诗歌形式创作的，我自己都从没试过。

麻省理工公开课 - 媒体、教育、市场课程节选