How to Use "unfailing" with Example Sentences

1. She fought the disease with unfailing good humor .
2. Kant 's theory of things in themselves is an unfailing question for study .
3. I have drawn strength and inspiration from your unfailing support .
4. A foolproof identification system ; the unfailing sign of an amateur ; an unfailing test .
5. Since he treated us with unfailing courtesy , we couldn 't very well do anything except return it ; approached as adults , we could not show ourselves childish .