hey anurag,
generally the terms which you mentioned are the best identifiers ,but as the tense would be different in the underlined portions so i get confused.I just want any tip to find with help of remaining sentence.

tip: for example i found this one:
Present perfect ends mostly with since and for
1.
I have known him for a long time
2.
we have lived here for ten years
3.
he has been ill since last week
4.
we haven't seen padma for last 8 months
something of tis sought guys>>>>

ckjakky wrote:Hey guys,
I get confused with these three basically present perfect and past perfect any tips to identify other than the basic has+ past participle Or similar stuffs

Yes, there are some techniques:

PRESENT PERFECT:

1. The action has started in the past and continues to present.

Example: The law has allowed the driver to drive with a high speed. --It was allowed in the past, and it still exists.

2. The action has occurred in the past, but its result remains int present.

It has rained. -----------------what is the result? ----The soil is still wet.

It rained. ----------------Why?---------------the soil is not wet. ---past action.........no result exists.

PAST PERFECT:

1. There will be two actions in the past. One of them happened earlier than other.

Action that happened earlier-------------past perfect...............More past.
Action that happened later..................past simple...............simple past.

Mind it there were two actions.

Example:

The train left the station after I had reached. ---Reached first----> then the train left.

They had come to see me before I went for MBA. ---come first ---------went later.

2. By + year + past perfect:

By 1990---------means there are some other activities before 1990.

So, by 1990 they had done the work.

--> It means that the work was started some times before 1990, and it had been completed within 1990.

Future Perfect:

--> There will be two actions in future. One of them will be performed earlier than the other.

The action that will be performed earlier will be in future perfect tense, and the action that will be performed later will be in simple future tense or present indefinite.

Example:
subject + shall or will have + past participle of verb = "I shall have gone to the store by the time you come."

HTH.