1.过去这里是一个超市。
   There ________ ________ ________ a supermarket here.
2.新加坡四分之三的人口是中国人。
    ________ ________ ________ the population in Singapore are Chinese.
3.你应该每堂课记些语法笔记。
   You should ________ some________ in every class.
4.高飞的社交活动影响了他的学习。
   Gao Fei's social activities got ________ ________ ________ of his studies.
5.Tom决定专攻汉语，因为他刚考试不及格。
   Tom decides to ________ ________ Chinese, because he just ________ the exam.