having been/has been/had been

[thestartupguy]

Can any expert discuss how/when to use having been/has been/had been with examples?

Also, is the sentence 'He invited criticism for himself after having written such an article in the news paper' correct?

Can anyone share links/article/GMAT materials that discusses the above in detail?

[imskpwr]

Can any expert discuss how/when to use having been/has been/had been with examples?

Check the difference in meaning and associated time frame.

1a.Jack is sick today.
Current status of Subject: sick

1b.Jack has been sick for three days
Current status Subject: sick
Past status(last 3 days only) of Subject: sick

2a.The door is open.
Current status of Subject: Open.

2b.The door has been open since 8 o'clock this morning.
Current status Subject: Open
Past status(after 8 O'clock) of Subject: Open

3.By the time Alex finished his studies, he had been in London for over eight years.
Past Status(by the time Alex finished studies) of Subject: over 8yrs in London
it gives the past status before another action in the past.

For time being, these details are sufficient.