YOU SAID:

i will be 87 you will be 89

INTO JAPANESE

私は87歳になります、あなたは89歳になります

BACK INTO ENGLISH

I will be 87 years old, you will be 89 years old

INTO JAPANESE

私は87歳、あなたは89歳になります

BACK INTO ENGLISH

I'm 87 years old, you're 89 years old

INTO JAPANESE

私は87歳、あなたは89歳です

BACK INTO ENGLISH

I'm 87 years old, you're 89 years old