My mother had bought me a new bucket of 'Nipton' paint to decorate my room, but I didn't like the colour because it was too dull.
To use the word "dull" in a sentence, you could say: "The lecture was so dull that I struggled to stay awake."
The knife is to dull to cut anything.
This is a very dull answer to your question.
Flat paint leaves a dull finish.
"The sky is looking dull today." "Talking to Joe is really dull." "Mary finds maths dull."
The quick-witted boy was by no means dull.
The actors did their best but the dialog was so dull that they couldn't save the play.
The envelope and its portentous contents fell onto the mat with a dull thud.
The banal lectures made the boy fall asleep because they were so dull and boring.
you can say my family and i went to the national forest and found a beautiful, but dull beech.
The Phantom of the Opera is a popular film.I found the opera dull and repetitive.
the root word is dull