【推荐1】John is a “problem child”. He often c_______ problems for his family.

【推荐2】—What do you think led to the car accident?
—It was the heavy fog that ________ it to happen.

【推荐3】Who ________ /kɒ:zd/the traffic accident last month?

【推荐1】— Where is my English book?   
— Sorry, I don’t ________(知道).

【推荐2】— ________ Mary have a sister?
—No, she ________.

【推荐3】I often b________ my teeth after I have dinner.

【推荐1】根据下列句子及所给单词的首字母写出所缺单词。(每空限填一词)
1. David runs fast, but Mike runs e__________faster.
2. Tom, keep q__________.Don't forget we are in the library now.
3. Mrs.Smith likes staying in her g__________to look after her roses.
4. People often s__________for information on the Internet nowadays.
5. Didn't you n__________the sign “No swimming”here? We can't swim in the river.
6. The teacher was p__________with the students and corrected their mistakes one by one.

【推荐2】Whether we will have a picnic on Sunday or not _________ (取决于) on the weather.

【推荐3】What ____ the people in the factory ____ (do) at that time?