Jack is a diligent worker.

A:ambitious B:lazy C:hardworking D:clever

Jack is a {{U}}diligent{{/U}} worker.

A:ambitious B:lazy C:hardworking D:clever

Jack is a {{U}}diligent{{/U}} student.

A:hardworking B:ambitious C:lazy D:slow

The project required ten years of (diligent) research.

A:hardworking B:social C:basic D:scientific

Jack is a {{U}}diligent {{/U}}student.

A:hardworking B:ambitious C:lazy D:slow

He is considered to be the most diligent student in class.

A:kind-hearted B:hard-working C:short-sighted D:far-reaching

Jack is a {{U}}diligent {{/U}}student.

A:hardworking B:ambitious C:lazy D:slow