单选题It is not enough onl

问题补充：

单选题Itisnotenoughonly______therulesofgrammarifyouwanttolearnEnglishwell.A.keeping in the mindB.to keep in mindC.to keep in your mindD.keeping in your mind

答案：

B解析keep sth. in mind 为固定短语，意为“记住，记在心里。”only to keep sth. In mind为动词不定式作主语。