dullness

例句：

1. 1. The old painting is so dull that it barely looks like anything.
   这幅旧画太沉闷了，几乎看不出是什么东西。
2. 2.His speech was so dull that he couldn't hold the audience's attention.
   他的演讲太枯燥了，无法吸引听众的注意力。
3. 3.The book was so dull that I couldn't finish reading it in one sitting.
   这本书太枯燥了，我一次都读不完。