----The boy never hasbreakfast.--It’sunhealthy habit.you must ask him to change it.A. /

----The boy never has breakfast.
----It’s unhealthy habit.you must ask him to change it.
A. /,an
Bthe ,an
C. / ,a
Dthe ,an

(答案→)A. /,anB. the ,anC. / ,aD. the ,an解析：句意：这个男孩从来不吃早饭。那是不健康的生活习惯，你必须让他改变。三餐、球类及学科名词前用零冠词。unhealthy的第一个因素是原因因素，结合句意，故选A.

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