1¡¢Unfortunately, when I dropped in, Doctor Li for Beijing to join in the fight against SARS, so we only had time for a few words.
A¡¢just left B¡¢has just left C¡¢is just leaving D¡¢was just leaving
2¡¢----If the traffic hadn’t been so heavy, I could have been back by 6 o’clock.
----What a pity! Tina here to see you.
A¡¢is B¡¢was C¡¢would be D¡¢has been
3¡¢He me that he here for twenty years by this year.
A¡¢told; will teach B¡¢tells; will have been teaching
C¡¢told; had taught D¡¢told; would have been teaching