It is natural that such a hardworking student should pass the exam.
这么用功的学生考试及格是很自然的事。
It is natural that he should fall in love with such a beautiful girl.
他爱上那位美丽的姑娘是很自然的事。
He's not our natural son we adopted him when he was three.
他不是我们的亲儿子－－他三岁时我们领养的。
