What are incomplete flowers missing?

It can be petals or sepals or pistil or stamens.

Explanation:

An incomplete flower is also known as imperfect flowers which is missing any of the parts like-petals, stamens, sepals or pistil. Structurally, a flower consists of these four main parts and missing of any parts in a flower make it an incomplete flower. Petals are leaf-like, colorful structures arranged at the top of the flower stem. Stamens are the male reproductive structure of a flower while pistil is the female reproductive part. Sepals are green colored leaf-like structure which can be found beneath the petal.