That's where you're just asked over a period of time, how often you eat this list of foods and you're given a very long list of foods.

正如同你们刚才问的,你多久吃一次这些食物,你有一个很长的食物列表

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

How often do you see him?

你多久见他一次？

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How often do you have this kind of fruit or vegetable?

多久吃一次这种水果或蔬菜

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

So how often do you drink sugared beverages?

你多久喝一次含糖的饮料

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

How often do you have this kind of cereal?

多久吃一次这种谷物食品

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选