Tại sao các nước đang phát triển thường có cơ cấu dân số trẻ?
Môn học
Chủ đề / Chương
Bài học
1.The students did the experiment, then they wrote report on it. => After... 2. She filled the basket, then she went ro the check out. => After... 3. They sang the song " Happy birthday " to her , then they gave her gifts =>Before... 4. My sister washed all the dishes, then she cleaned the kitchen. =>Before... 5. We paid the bill, then we left the restaurant. =>After...