老皇历
Out of date
【注音】lǎo huáng lì
【解释】过了时的皇历，比喻过了时的事或规定。
An out of date calendar is a metaphor for obsolete practice or regulation.
【例子】
例：
A：听说外国人去公园玩儿买的票跟中国人不一样？
B：那已经是老皇历了。

Ex.
A：They say a foreigner in China has to pay a different price for park entrance ticket, is that so?
B：That’s an obsolete practice.


冷门儿
Unpopular
【注音】lěng ménr
【解释】少有人注意的事。
Something that receives little attention.
【例子】
例：当时我考法律专业时，还是个冷门儿。
Ex.：When I chose to major in Law at that time, it was an unpopular branch of learning.