To Be or Not To Be - the most useful verb

Uppercase Lowercase Pronunciation Meaning
ΕΙΜΑΙ είμαι imay I am
ΕΙΣΑΙ είσαι isay You are
ΕΙΝΑΙ είναι inay He/she/it is
ΕΙΜΑΣΤΕ είμαστε imastay We are
ΕΙΣΤΕ είστε istay You are
ΕΙΝΑΙ είναι inay They are

To make a verb negative add ΔΕΝ (δεν) in front of the verb. Hence "Δεν είμαι" (ΔΕΝ ΕΙΜΑΙ)means "I am not"