Short forms of adjectives are formed by dropping the long form (two
letter) ending of the adjective, and adding the appropriate gender
ending.
long
short
здоровый
здоров
хороший
хорош
готовый
готов
The resulting form will be masculine. To get the feminine,
neuter and plural forms, you would add the appropriate one
letter gender ending.
When forming short form adjectives you should always obey the spelling
rules.
Masculine forms of short adjectives that end in a consonant cluster will have
a fill vowel.
согласный - согласен - согласна
Short form adjectives in Russian are used primarily as predicates:
they go with the verb 'to be', rather than with a noun. Compare the
two sentences: This man is interesting.
Этот человек интересен. This interesting man is my uncle.
Этот интересный человек мой дядя.
Generally speaking, short form adjectives describe a temporary state (sick,
ready).
Сегодня я болен. Today I'm sick
Они ещё не готовы. They are still not ready.