Habitual, habitual
惯常───Customary;经常───often
In the late Middle Ages, it was customary to scrape away the surface of the parchment with an abrasive, which completely wiped out any writing that was there.───在中世纪后期，人们习惯用磨料刮去羊皮纸的表面，把纸上的所有文字都擦得干干净净。
In the United States, it is not customary to telephone somenone very early in the morning.───在美国，人们不习惯在大清早给人打电话。
It is customary to offer a drink or a snack to guests.───通常用饮料或小吃招待客人。
At age seven, as is customary in Sparta. . . the boy was taken from his mother and plunged in a world of violence.───在七岁的时候按照斯巴达的惯例，男孩将被从他母亲身边带走，投入无间炼狱之中。
It is often customary, when one has a new idea, to ask if Dirac hasn't done something in this area.───当一个人有了什么新想法，习惯性的做法是，向别人问一下狄拉克在这个领域是否做过什么工作。
With his customary regal manner, Duke, smiling coolly, answered, "I guess things would have been different if I'd been a white man. "───而公爵不动声色，微微地笑道：“如果我是个白人，我想结果应该是截然不同的。”
It is customary for the teacher to provide grammar notes to help the student generalise what he has learned.