（需要说明原因）

题目

（需要说明原因）
1,I saw some chidren______ football when I waled past.
A are playing B played C playing D is playing
2,I asked the girl to join us again and again ,_____ she didn't.
A but B so C then D however

答案

1.选C,see sb.doing sth看到某人正在做某事,符合题意.
2.选A,转折关系,如果要选D,应该在however,后加逗号