slow to learn or understand; lacking intellectual acuity
示例
so dense he never understands anything I say to him|never met anyone quite so dim|although dull at classical learning, at mathematics he was uncommonly quick|dumb officials make some really dumb decisions|he was either normally stupid or being deliberately obtuse|worked with the slow students
so lacking in interest as to cause mental weariness
示例
a boring evening with uninteresting people|the deadening effect of some routine tasks|a dull play|his competent but dull performance|a ho-hum speaker who couldn't capture their attention|what an irksome task the writing of long letters is|tedious days on the train|the tiresome chirping of a cricket|other people's dreams are dreadfully wearisome
