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。
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。）
