Word Formation   (John Sinclair)

 Making new words by adapting old ones is very popular at present.

By learning suffix and prefix you can gain this goal. 

-able: combines with verbs to form adjectives.

Adjectives formed in this way describe someone or something that is effected by the action or process described by the verb.

For example, if something is 'avoidable', it can be avoided.

admirable: (adj.) having many good qualities that you respect and admire.

eg. It is an admirable book, the first to tell the whole truth about the war.

disposable: (adj.) intended to be used once or for a short time and then thrown away.

eg. disposable nappies

irritable: (adj.) getting annoyed quickly or easily [= crabby].

eg. Jo was tired, irritable, and depressed.

preferable: (adj.) better or more suitable

eg. In warm weather, clothes made of natural fabrics are infinitely preferable.

tolerable: (adj.) a situation that is tolerable is not very good, but you are able to accept it

eg. The heat in this room is barely tolerable.

variable: (adj.) likely to change often:

eg. Expect variable cloudiness and fog tomorrow.

( from mis.bitarafan )