問問有關英文時態問題

如果你沒有說明時間多久，或從何時起，不如簡單D用present continuous tense.
I am washing dishes.
如果用present perfect continuous tense, 通常也會描述事情至今，發生了多久。
eg1: I have been washing dishes for a few minutes.
eg2: I have been washing dishes since I finished dinner.

2015-03-09 21:25:15 補充：
From www.englishpage.com
2. ..." Without the duration, the tense has a more general meaning of "lately." ...
eg, Recently, I have been feeling really tired. --- it is ok
BUT I don't think Leo means "Recently, I have been washing dishes."
-------Just a friendly discussion--------

2015-03-09 21:29:42 補充：
Recently, I have been washing dishes. = 最近，我一直在洗碗。

The present perfect continuous shows that the action of washing began in the past, has extended up to the present and may continue in the future.
It does indicate the possiblity of continuation in the future Or you're fired.
When the speaker purposely use the present perfect continuous to express impatient to start,to finish the (20-1=19) dishes impatient because of the delay in speaking now,in an impatient abrupt manner of "recently","lately", "without a duration";then the speaker should say anxiously:-
eg:-She has been washing dishes lee.

You can use Present Perfect Continuous :)

1.We use the Present Perfect Continuous to show that something started in the past and has continued up until now. "For five minutes," "for two weeks," and "since Tuesday" are all durations which can be used with the Present Perfect Continuous.

Examples:
They have been talking for the last hour.
She has been working at that company for three years.

2.You can also use the Present Perfect Continuous WITHOUT a duration such as "for two weeks." Without the duration, the tense has a more general meaning of "lately." We often use the words "lately" or "recently" to emphasize this meaning.

Examples:
Recently, I have been feeling really tired.
She has been watching too much television lately.