。
She looked at his face.
Literal
She [topic-は] his [genitive-の] face [object-を] saw.
About as minimal a Japanese sentence as you can get with 5 elements: subject (彼女) + topic marker (は) + possessor (彼の) + object (顔を) + verb (見た). A useful baseline structure — the same skeleton with added adverbials, mimetics, or compounds becomes 'glanced at,' 'stared at,' 'gazed at,' 'looked sideways at.'