A.現在完成進行時用於表示動作，這個動作持續了一段時間。
B.have的現在+been+-ing形式
positive form:I have been waiting.
negative:I haven't been waiting.
question:have I been waiting?
C.
現在完成時用於表示一直持續到現在的動作。We've been waiting here for twenty minutes.
現在完成進行時可以表示迄今爲止的重複性動作。Natasha has been playing the piano since she was four.
還可以用現在完成進行時表示剛剛結束的動作。 I've been swimming.That's why my hair is wet.
D.for,since,how long & recently
for : My sister has been staying with me for three weeks now
since : You have been playing on that computer since seven o'clock.
how long用於疑問句: How long have you been waiting?
注意recently和lately。（表示過去的時間裏）
I haven't been feeling very well recently.
What have you been doing lagely?