The elderly woman thanked me for helping her cross the road.

Literal

Elderly-woman [topic-は], road [object-を] cross [nominalizer-の] [object-を] helped [nominalizer-こと] [toward-に対して], me [to-に] thanked.

Multiple nominalizations nest inside each other: 横断するの is the object of 手伝った, and the whole event is packaged by こと to serve as the target of 感謝する via に対して. Grammatically dense despite everyday content.