11. David had gone home before we arrived. After ……………………………………………………………………………………. 12. We had lunch then we took a look around the shops. Before …………………………………………………………………………………… 13. The light had gone out before we got out of the office. When……………………………………………………………………………………. 14. After she had explained everything clearly, we started our work. By the time ……………………………………………………………………………. 15. My father had watered all the plants in the garden by the time my mother came home. Before …………………………………………………………………………………. 16. “It is the first time I have eaten sushi”, said Bill. Bill said ……………………………………………………………………………. 17. “I broke my glasses yesterday”, said Lan. Lan said that ……………………………………………………………………………. 18. I couldn’t attend the evening classes because I worked at night. → If I (not work) …………….. at night, I (attend) ………………….. the evening classes. giúp mình với các bạn ơi