1The professor's monotonous voice made it difficult for students to stay awake during lectures.
2Is the work monotonous, or does it involve a variety of tasks and challenges?
3The landscape became increasingly monotonous as we drove through the endless plains.
4Try to avoid a monotonous tone when presenting your research findings to a general audience.
5There is a risk that relying too heavily on automation could make many jobs monotonous and unfulfilling.