This is the 14335th most frequent Korean word.
못하겠다는데
"It means 'saying that one cannot do (something).'"
The phrase "못하겠다는데" in this sentence indicates that the subject is expressing difficulty or inability to perform an action (here, cooking).
그가 요리를 못하겠다는데 같이 도와줄 사람이 있나요?
He says he cannot cook; is there someone to help him?
The word "못하겠다는데" is used to quote someone's statement of inability (here, exercising).
그녀는 더 이상 운동을 못하겠다는데, 왜인지 궁금합니다.
She says she cannot exercise anymore; I wonder why.
The usage of "못하겠다는데" here reflects a conveyed message from the children about their inability to complete homework.