Because his family was poor, he left school -> Because of

Because his family was poor, he left school

⇒    $Because$ $of$ $his$ $poverty$, $he$ $dropped$ $out$ $of$ $school$.

⇒   Tạm dịch : Vì quá nghèo, anh ấy đã phải bỏ học.

⇒   $Because$ $of$ : Vì 1 điều gì đó.

$#BearChan$