The phrase "convenient thing" is correct and usable in written English.
It is typically used to describe a beneficial or useful object, process, or idea. For example, "Having a laptop computer is a very convenient thing for students who need to take notes in class or do research online."
So the convenient thing has been to ignore her.
Nancy Hopkins, who led the effort, said last week: "The convenient thing would have been to say it wasn't true.
A little pot of kirmizi biber flakes is an incredibly convenient thing to have in the kitchen.
The convenient thing about the unknown, from a budgetary standpoint, is that it always exceeds the known.
He refuses to do the politically convenient thing because he believes it is wrong – and pays with his life.
At 22cm (9 inches) long, 464 pages deep and weighing in at more than half a kilogram, it isn't a convenient thing to lug around.
One of the liveliest places to hear the latest dancehall reggae, even if neither the place nor the time is convenient: things don't really get going until after midnight.
And one of the most convenient things about having a morning-style meal at midday is how easy and affordable the ingredients are to grab from the shop on your way in to work, if your fridge at home is bare.
One of the most convenient things about Google Maps is that it integrates various forms of transportation into its directions.
"So convenient a thing it is to be a reasonable creature, since it enables one to find or make a reason for everything one has a mind to do," he once wrote.
Benjamin Franklin commented in his autobiography on those who have made similar arguments to yours, noting: "So convenient a thing it is to be a reasonable creature, since it enables one to find or make a reason for everything one has a mind to do".
