A:浙江省某外向型企业
B:一个到上海参观世博会的美国人
C:中华人民共和国商务部
D:一位即将赴美国留学的中国大学生
He was just falling asleep _____ there was a loud knock on the door.
He ____(lie) down on the bench and soon fell asleep.
too much sugar is bad your teeth.