How can you use the word diagnose in a sentence?

1. Doctors use a variety of techniques to diagnose illnesses.

2. The mechanic was able to diagnose the problem with the car quickly.

3. After running some tests, the doctor was able to diagnose the patient with a rare disease.

4. The company brought in a consultant to diagnose the problems with their business.

5. The teacher used a variety of assessment tools to diagnose the students' learning difficulties.