IPA: /ˈhæpən/
KK: /ˈhæpən/
To occur or take place, often unexpectedly or by chance.
I wonder what will happen at the party tonight.
Past: happened
Past Participle: happened
Happen → The word originates from the Middle English 'hapnen', which is derived from 'hap' (meaning chance or fortune) and the suffix '-en' (indicating a verb form). Thus, 'happen' means to occur by chance or to come about unexpectedly.
Think of 'hap' meaning chance, and remember that 'happen' refers to something that occurs by chance.