6PHRASE (在耗时且无关紧要的事情上)一丝不苟，注重细节 If you say that someone dots the i's and crosses the t's, you mean that they pay great attention to every small detail in a task; often used to express your annoyance because such detailed work seems unnecessary and takes a very long time. (在耗时且无关紧要的事情上)一丝不苟，注重细节
7PHRASE 很久以前The year dot is used to mean a very long time ago. 很久以前 [British, informal]
You've wanted to be a barrister since the year dot.