。
She's a skilled skier.
Literal
She [topic-は] skiing [subject-が] skilled.
The kanji 上手い (うまい) is the i-adjective form for 'skilled / good at' — distinct from the na-adjective 上手 (じょうず) despite sharing the kanji 上手. The two have similar meanings but slightly different usage patterns: うまい is more colloquial and emphasizes effective execution (and overlaps with 美味い 'tasty'); 上手 (じょうず) is more formal and tends to praise overall skill. The shared kanji creates a visual ambiguity that depends on context to resolve — an unusual case where the same kanji compound has two different inflectional patterns.