现在完成进行时：
1．构成：have / has + been + 现在分词
2．功能：
（1）表示从过去某时开始发生，一直延续到现在且可能延续下去的动作。 （最好将此定义读 5遍）
?. I've been waiting for an hour but she hasn't come.
?. He has been running after her for 8 years.
（2）表某种感情色彩。
?. I've been wanting to see you for so many years.
?. Who's been telling you such nonsense.
现在完成时与现在完成进行时的对比：
现在完成时强调“结果”，而完成进行时强调“动作的延续”。
?. I have thought of it.（我已想到了这一点。）
?. I have been thinking of it.（我一直在想这一点。）
?. Jim has painted the door.（杰姆已将门油漆过了。）
?. Jim has been painting the door.（杰姆一直在油漆门。）
测试精编
1. They ________ us since five o'clock this morning.
A. are helping B. have been helping
C. have been helped D. have helped
2. I ________ the book the whole day, yet I haven't finished it.
A. have been reading B. have read
C. am reading D. had been reading
3. Please come in. We ________ about your paper.
A. talk B. had been talking
C. have been talking D. would have talked
4. Such natural resources as coal and petroleum ________.
A. gradually are exhausted B. are being gradually exhausted
C. have gradually exhausting D. have been exhausting gradually
5. It ________ almost every day so far this month.
A. is raining B. rained C. rains D. has been raining
用所给动词正确时态填空：
1. You should go to bed. You ________ (watch) TV for 5 hours.
2. I ________ (write) letters since breakfast.
3. I ________ (write) 3 letters since breakfast.
4. Sorry, but Mr. Smith ________ (leave) for Beijing.
5. I ________ (look) for him everywhere, where can he be?