Hi Tumed,

The important point in this Kwiziq lesson is the agreement of the adjective with the noun (feminine ones in this case) by adding an -e.

Chat is masculine and you would use the adjective 'gros' rather than 'grand' which is used for height normally.

Un gros chat ------> une grosse chatte  ( here you add -se, not covered in this lesson)

Un grand homme----> une grande femme

Hope this helps!