The phrase "act mainly" is correct and usable in written English.
It can be used to describe the primary function or role of someone or something in a particular context.
Example: "In this organization, we act mainly as facilitators to help teams achieve their goals."
Alternatives: "function primarily" or "operate chiefly".
Drugs which act mainly centrally, such as narcotic analgesics, inhibit both phases, while peripherally acting drugs, such as indomethacin, only inhibit the late phase.
Antidepressant drugs act mainly by blocking the noradrenaline and/or serotonin uptake sites and require a chronic treatment.
No longer happy to act mainly as middlemen, many have wanted a slice of the action themselves.
These substances act mainly through mechanisms that result in the release of catecholamines from their storage areas in nerve terminals.
This makes them a comedy act, mainly for people who would accept AC/DC only as some sort of guilty pleasure.
And since tobacco companies here act mainly as distributors, the industry has no local lobbying power to create opposition within the government, he argued.
Jack Kiefer-Bandr and co shoot from lip and hip with the customary fast-cut, ever-ratcheting tension, though a few do act mainly with their jaws.
His act mainly targets current events and the local political scene – which, believe me, is quite a generous source of comedic material.
The Australian federal government is currently consulting on introducing a bill of rights – called a human rights act – mainly based on the UK model.
But Compaq Computer is aiming its new iPAQ Pocket PC H3150 at people who want their palmtop computers to act mainly as, well, palmtop computers.
The ECs are phospholipid-derived lipids that can be produced by any cell type and organ and act mainly as paracrine mediators.
