一、单项选择（共15小题；每小题l分，计15分）在下列各题A、B、C、D四个选项中选择一个能填入题干空白处的最佳答案．
1．﹣﹣﹣Could you tell me something about Switzerland？
﹣﹣﹣Oh，it is _______ European country with a beautiful environment．（ ）
A．an B．a C．the D．/
2．With the _____ of the washing machine，people have had more free time to relax．（ ）
A．invention B．situation C．condition D．tradition
3．﹣﹣﹣We couldn't find you anywhere around 8o'clock yesterday evening．
﹣﹣﹣I'm sorry for that．I _____ in the supermarket then．（ ）
A．shop B．am shopping C．was shopping D．will shop
