The phrase "incapable in" is grammatically correct and can be used in written English.
It is typically used to indicate a lack of ability or skill in a certain area. Example: She was completely incapable in math, so she always struggled to pass her math tests.
The prime minister's son Euan Blair was yesterday reprimanded by police for being drunk and incapable in London's Leicester Square.
Four years ago his son Euan, then aged 16, was reprimanded by police, having been arrested for being drunk and incapable in a Leicester Square gutter.
The core of the United Nations force is expected to be the 6,000 regional African troops already deployed, though a Pentagon official called them "completely incapable" in remarks to Congress in April.
The detail is relevant to why City are incapable in Europe while very capable across the course of a domestic season because it reveals why Mancini's players don't look like they'll run through walls for this boss.
But when Abbot and Nixon start their sparring, Mond's film takes on a magnificently physical and tactile quality, as Gail becomes frail and incapable in her son's powerful arms.
She wanders from classical mythology to the Venerable Bede's sparrow to an acute paragraph of literary criticism concerning the multiple meanings of the word "incapable" in Gertrude's description of the drowned Ophelia.
He is incapable of filling in a tax return.
He's psychologically incapable of giving in to Fehr and making a reasonable deal".
"I'm not incapable of putting in a good day's work and watching my baby grow," he said.
"We treat it as an earnest but incapable ally in the war on terrorism".
But if I became mentally incapable or in the way of progress, I think that I would be told that".
