After être, the verb you'll need most is avoir, to have. It's irregular too:

Pronoun	Avoir	English
j'	ai	I have
tu	as	you have
il / elle / on	a	he / she has · we have (on)
nous	avons	we have
vous	avez	you have
ils / elles	ont	they have

Ai starts with a vowel, so je always becomes j': j'ai, never je ai.

• J'ai un plan de Paris. — I have a map of Paris.
• Marcos a un chien. — Marcos has a dog.
• Tu as un téléphone ? — Do you have a phone?