verb form

[FFP]

I want to know what's the meaning of ' It's long been part of '.

[Dippit]

Hi,
This is quite literal - it means that it's been part of/included in something for a long time.
For example, 'it's long been part of the Chinese culture to exercise outdoors' means that they have been exercising outdoors for a long time. The exact time involved isn't important.
Hope this helps,
Dippit