。
She put on a coat.
Literal
She [topic-は] coat [object-を] put-on.
Bare bones, but instructive for the verb choice. 着る is the wearing-verb for items worn on the torso (coats, shirts, dresses) — distinct from かぶる (for things on the head: hats, helmets), 履く (for things on the feet/legs: shoes, pants, socks), する (for accessories: ties, watches, gloves), and かける (for things hooked over: glasses, scarves). Each garment maps to a specific verb, and using the wrong one is one of the most distinctively non-native-sounding mistakes a learner can make. The polite past ~ました places this in everyday-polite register.