be in apple-pie order
US /bi ɪn ˈæp.əl.paɪ ˈɔːr.dər/
UK /bi ɪn ˈæp.əl.paɪ ˈɔːr.dər/

1.
井然有序, 整洁如新
to be perfectly neat, tidy, and organized
:
•
After she cleaned the house, everything was in apple-pie order.
她打扫完房子后,一切都井然有序。
•
The manager likes to keep his office in apple-pie order.
经理喜欢把他的办公室整理得井井有条。