why bamboo and maize are considered as grassses?

Answer 1

GRASSES OF USE

The strength and flexibility of grasses and even some reeds finds application in weaving. Mats and baskets can be made from them. The Pattamadam pai is made from korai grass. African tribals wear grass skirts.

Bamboo and sugar cane are giant grasses. Bamboo regenerates quickly and the hard stems are a cheap and convenient resource for making furniture, baskets and screens. Bamboo stems are edible and the material of which flutes are made. After extraction of sugar, the crushed stems of the sugar cane, known as bagasse, are used in making paper.

Answer 2

They are genetically close to grasses.