正确的句子是：
To our great joy, his father has been cured of his lung cancer
cure of 是习语,
意思是 （病症被）治愈
固定介词是 of
The old temple under repair dates back to the ming dynasty
under repair 是对的,
意思是 正在（被）进行维修
under 是固定介词.
dates back 的 date 要用第三人称.
dates back 的意思是
追溯到,（历史）可以追溯到
希望帮到了你.