The phrase "a formidable box" is correct and usable in written English.
It can be used to describe a box that is impressive, powerful, or intimidating in some way.
Example: "The magician pulled out a formidable box from the back of the stage, captivating the audience's attention."
Alternatives: "an impressive box" or "a powerful box".
Despite formidable box office – it's grossed $167m£109m9m) Stateside, more than the other four nominees combined – most voters weren't as jazzed, with even Gillian Flynn's seemingly assured screenplay nomination falling by the wayside.
The Army Special Forces Underwater Operations School is located in Key West, Florida, which also hosts a formidable population of box jellyfish.
An expert in software-defined radio — the modification of radio signals with a computer, as opposed to mixers, amplifiers, and other hardware — Humphreys used a general-purpose processor to build what he calls a "formidable lying machine," a box that "listens" to the G.P.S. signal, gradually builds a bogus signal that aligns perfectly with the real, and then slowly overtakes it.
An expert in software-defined radio the modification of radio signals with a computer, as opposed to mixers, amplifiers, and other hardware—Humphreys used a general-purpose processor to build what he calls a "formidable lying machine," a box that "listens" to the G.P.S. signal, gradually builds a bogus signal that aligns perfectly with the real, and then slowly overtakes it.
Vietnam's street markets, which sell everything from live frogs to toilet paper, remain a formidable foe for big-box hopefuls.
A formidable figure in American press boxes during my Sports Illustrated years was Jerome Holtzman of The Chicago Tribune.
Home Depot is a formidable competitor (see "Profit in a Big Orange Box").
With Holm's background in traditional boxing and kickboxing, Tate was a formidable opponent with her prowess in jiu-jitsu and wrestling.
"He's a formidable candidate".
That was a formidable problem.
