他们的长子今年大学毕业了。

Their ___firstborn graduated from college this year.

作为家里的长子，他总是照顾弟弟妹妹们。

As the ___firstborn, he always takes care of his younger siblings.

作为长子，他从小就承担着照顾弟弟妹妹的责任。

As the ___firstborn son, he took on the responsibility of caring for his younger siblings.