He had retained a keen interest in the progress of the work.

他一直对工作的进展保持着强烈的兴趣。

He took a keen interest in his grandson's education.

他对孙子的教育很感兴趣。

She has a keen interest in art.

她对艺术非常感兴趣。

He has a keen interest in gardening.

他对园艺非常感兴趣。

He looked at the picture with keen interest.

他饶有兴趣地仔细端详着这幅画。