ellipsis: Leaving out words when their meaning can be understood from the context.

e.g. (it is) Nice day, isnt it?

   gender: the use of different grammatical forms to show the difference between masculine,feminine and neuter ,or between human and non-human.

e.g. he, she, it, who, which

gradable: pretty, hard or cold are gradable adjectives: things can be ,hamore or less pretty  or cold. adverbs of degree (like  Rather , Very) can be used with gradable words . perfect or dead are not gradable words : we do not usually say that something is more or less perfect ,or very dead.