The phrase "a common flag" is correct and usable in written English.
It can be used to refer to a flag that is widely recognized or used by a group, organization, or country.
Example: "The United Nations uses a common flag to represent its mission of global peace and cooperation."
Alternatives: "a shared flag" or "a universal flag".
The most common flag used by the trade unions and other protesters was the red flag of revolt.
Jefferson Davis, former President of the Confederate States of America, concurred, "My pride is that that flag shall not set between contending brothers; and that, when it shall no longer be the common flag of the country, it shall be folded up and laid away like a vesture no longer used".
Emotional retreat is a common red-flag precursor to marital affairs and/or divorce.
Many flags can be traced to a common origin, and such "flag families" are often linked both by common traditions and by geography.
On top of the caravan was an aerial, and attached to the aerial, blowing in the wind that was coming off Morecambe Bay, was a St George's cross, the English national flag – a common sight now across the nation, though I'm sure it never used to be when I was young.
Writing a physical description of the layout for the Gettysburg National Cemetery under construction in November 1863, the correspondent from the Cincinnati Daily Commercial described the dividing lines between the state grave plots as "the radii of a common center, where a flag pole is now raised, but where it is proposed to erect a national monument".
Outside, hundreds of people protested, holding both Mexican and American flags, a common sight in my neighborhood, and in adjacent Riverside County, where people also fly black P.O.W.-M.I.A. flags and banners for Los Dodgers, Los Lakers, and the Raiders.
A common design involves the current flag of Greece and the pre-1978 flag of Greece with crossed flagpoles and the national emblem placed in front.
BILL EARLY Writing on BusinessKnowHow.com, Janet Attard flags a common mistake small businesses make.
