问题
选择题
—Tom enjoys__________basketball on Sunday afternoons，doesn’t he?
—Yes，he does.But what his sister enjoys__________.
A．to play；dancing
B．playing；to dance
C．to play；to dance
D．playing；is to dance
答案
A
address所表示的动作发生在谓语动词所表示的动作之前,且与letter之间逻辑上存在着被动关系,having been addressed...在句中作非限制性定语。