The phrase "deeply isolated" is correct, and it can be used in written English.
You could use this phrase to describe a person or a place that feels lonely and cut off from the rest of the world. For example, "The small mountain village was deeply isolated, and the residents rarely had contact with anyone outside their own community."
But Robben Island remained deeply isolated – isolation worsened, Mandela wrote, by the proximity of "the glass towers of Cape Town.
Deeply isolated, they spoke Russian and Bukhori, a hybrid of Farsi and Hebrew.
A premature unilateral attack could upend everything and one result of many would be an Israel under fire, under attack, and more deeply isolated than ever before.
On the contrary, Mr. Obama said, he had deeply isolated the Iranian authorities and had helped to press them to resume negotiations.
Madagascar, a former French colony off the coast of southern Africa with 20 million residents, has been deeply isolated since the coup.
The scenes across the country illustrated the complexity of the three-month crisis in Syria, which has deeply isolated Mr. Assad's leadership.
It's an act of startling self-confidence, but a deeply isolating one as well.
Interviewed on CNN, McDonough said the US would work with South Korea, Japan, China and Russia "to deeply isolate the North Koreans" and "squeeze" them until they lived up to prior commitments to get rid of their nuclear weapons.
By contrast, the modern countryside can be deeply isolating; a place where people drive their children to school, shop in retail parks and spend their evenings watching satellite television.
They now live a deeply rural, isolated existence in County Wicklow, Ireland, with summer forays back to New York, where they keep an apartment.
Freeman manages to combine an investigation of Augustine's "deeply pessimistic, isolated and guilt-ridden mind" with an account that does justice to his genius.
