The phrase "and it is closely" is grammatically correct and can be used in written English.
You can use it when you want to indicate that something is closely related or connected to another subject or idea.
Example: "The research findings are significant, and it is closely linked to the ongoing studies in this field."
Alternatives: "and it is tightly" or "and it is intimately".
Performance art has its origins in the early 20th century, and it is closely identified with the progress of the avant-garde, beginning with Futurism.
It is prescribed to a million patients for the treatment of chronic pain, and it is closely regulated at every stage of its manufacture and distribution by the Food and Drug Administration and the Drug Enforcement Administration.
It has now become larger than both Cyber Monday and Black Friday combined, and it is closely watched as a barometer of the company's performance.
As John Cassidy writes, Mitt Romney has "a Chris Christie problem" at the moment, and it is closely related to what Cassidy calls his "FEMA problem".
Like Scottish Gaelic, Manx was an offshoot of Irish, and it is closely related to the easternmost dialects of Irish and to Scottish.
Wardha is situated on major routes between Nagpur and Mumbai Bombayy), and it is closely linked with the history of Nagpur.
But Google Drive isn't purely about storage; it's also where Google productivity apps live, and it's closely linked to its photo sharing/storage tools and Gmail, all of which share the same pool of available online storage.
Only those guests approved by Wasserman would be invited; M.C.A. had developed a computerized list of contributors, and it was closely guarded.
Clarins launches Instant Light Lip Comfort Oil (£18.50, clarins.co.uk) this week and it's closely followed by YSL's Volupte Tint in Oil (£23.50, yslbeauty.co.uk, which launches on 28 January).
Only one major QTL (i.e., qPM2) was detected for powdery mildew resistance, and it was closely linked to markers CMBR120 and CSJCT358 (Fig. 3).
At 1 day after exposure to 60 °C, the compressive strength reduction was observed in all specimens, and it was closely related to the conversion of CAH10.
