簡單英文..........................

have been : present pefect
指你曾經做過嘅事, 可能而家仲做緊, 或已經完成冇再做
而 had been: past pefect
都係指你曾經做過嘅事, 但肯定已經完成, 或已經冇再做.
ex: I have been sick 你曾經病 ( 可能而家仲病緊, 或已經好番冇病)
I had been sick 你曾經病 ( 肯定你而家已經好番, 冇病)

1. has been and have been----- 是verb to be 的 現在完成式。
現在完成式 Present perfect tense 是表示該活動由過去連結到現在.
a connection with now 和 to give new information or to
announce a recent happening. 剛剛發生 just 亦會用到這tense.
例句：The road is closed . There has been an accident.
(表示剛剛發生意外)

2. had been----- 是 verb to be 的 遇去完成式。
過去完成式 past perfect tense 是說那件事在過去某段時間發生。
something that happened in the past 和 things happened before
at a period of time.
例句： May had just got home when I phoned. She had been
in London. (注意全句發生在過去)

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1. 完成式 Perfect tense 很多時要比較 2 個 verbs 動詞的先後時間。
2. 由於 has been, have been , had been 是 verb to be 的 perfect
tense, 所以你要明白 verb to be 的用法。
3. 有關verb to be 的用法可到 知識+ 或其他網找。我以前答過。

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如上文所講 , 在過去的時態裏, 一直在做的一件事 , 用 had been, 在現在時態裏 , 一直在做的一件事, 用 have been or has been.

e.g. I have been living there since 1980.
自 1980 年 , 我一直都住在這裏
(你現在仍然住在這裏)

e.g. We have been talking all day.
我們整天一直在談.
(現在還未談完)

e.g. It has been raining cats and dogs.
這一直在下大雨中
(現在還在下大雨中)

e.g. When she arrived, I had been waiting for three hours.
當她到的時候 , 我一直在等了三小時.
(講述之前我一直等了她三小時直至她到達時)

e.g. I realized that I had been overworking, so I decided to take a couple of
days' holiday.
我察覺到我一直工作過多了 , 所以我決定去放幾天假期
(講述之前我一直工作過多)

e.g. He had been hiding the truth until his mom had realized that.
他一直在隱瞞事實直至他的媽媽發現了這事實.

e.g. She had been cheated by her son until she had realized that.
她一直被她的兒子欺騙直至她察覺了
(由於是被動式 , 所以是 had been cheated )

e.g. He had been chosen as the leader since he studied at Form 1.
自他就讀中一時 , 他一直被選為領袖
(講述他一直被選為領袖是由中一開始)


希望以上例子令你明白多一點

HAVE BEEN 係現在完成進行式
用係過去到現在都係度做GE時態
EXP:He has been eating for three hours.
中文:佢到依家已經食左三個鐘GE野

HAD BEEN 係過去完成進行式
用係過去到過去的某一時間的持續
EXP:He has been eating for three hours before the waiter came.
中文:服務員黎之前佢已經食左三個鐘GE野

HAD BEEN就係描述之前發生GE野
而HAVE BEEN就係依家都係度發緊GE野
兩者相同地方都係持續發生

had been and have been 意思上基本冇分別, 但文法上卻有不同.
for example: When I was ......, I had been .......
由於前句用 "was", 因此要配對時式 (Tense).
如果前句用 "is", 則要用現在式 (present tense)了.

希望能夠解答你的疑難 ^^