If the library were open until later, it would be nice to study there.
If I thought the library stayed open a bit later, I would like to go there to study.
ーIf the library were open until later, it would be nice to study there.
「遅くまで図書館が開いていたら、そこで勉強できるといいのに。」
library で「図書館」
open until later で「遅くまで開いている」
ーIf I thought the library stayed open a bit later, I would like to go there to study.
「もうちょっと遅く前図書館が開いていたら、図書館に行って勉強したいのに。」
stay open「開いている」
a bit later で「もう少し遅く」
ご参考まで！
カナダ 
