（2012四川绵阳）________I was in the US，I made a lot of American friends．
A．While
B．Although
C．Unless
D．Until
（2013天津）—I don’t know________．
—Because he has to look after his mother．
A．why he is leaving
B．why is he leaving
C．whether he is leaving
D．whether is he leaving
（2014甘肃兰州）She________to an English program while her parents________TV．
A．was listening；is watching
B．listened；were watching
C．was listening；watched
D．was listening；were watching
（2014广东）—I didn’t see you at the beginning of the party last night．
—I________on nay biology report at that time．
A．worked
B．work
C．was working
D．am working
The girl was flying a kite________her father came back．
A．when
B．while
C．until
D．after
—I went to see you yesterday evening．But you weren’t in．Where were you then?
—I’m sorry．I________a walk by the lake with my classmates．
A．am taking
B．was taking
C．take
D．took
