The phrase "always been sustained" is correct and usable in written English.
It can be used to indicate that something has consistently been maintained or supported over time.
Example: "The community's commitment to environmental conservation has always been sustained through various initiatives and programs."
Alternatives: "has consistently been upheld" or "has continually been maintained."
The vitality of motion pictures has always been sustained by craftsmen with a modicum of business sense and the ability to tell a good story.
My own interest in Liszt has always been sustained by his sometimes bizarre balancing act between fulfillment and insufficiency, between genius and empty gesture.
Racing has always been sustained by being a brilliant vehicle for a bet, a way of playing the market but in the open air instead of tethered to a computer screen, involving real money going on a beautiful creature of flesh and blood and guts and ability.
The authority of this proclamation, so far as it respected this continent, has never been denied, and the titles it gave to lands have always been sustained in our courts.
But the challenge for Chrysler, which has a history of near-death experiences, has always been sustaining its turnarounds.
He realizes that a cabin in Maine would deliver him back to the natural world that has always been sustaining.
One notorious problem with aid groups is that they introduce new technologies that can't always be sustained; the developing world is full of expensive wells that don't work because the pumps have broken and there is no one to repair them.
The fact that the post-Arab Spring Middle East is unstable today in ways that make our Reagan-era and Clinton-era approaches seem obsolete does not prove those approaches were misguided at the time; it just proves that what worked decently in one generation can't always be sustained into the next.
Because smart, educated types "believe they should have the power to tell you what to do," whereas values voters "will always be sustained through two institutions, the church and the family"—meaning they think the church and the family should have the power to tell you what to do.
Gaming is business, fundamentally, and any series that does big numbers is always going to be sustained.
Her high notes were not always secure enough to be sustained, but they were there.
