the ins and outs
A:Peter really is a remarkable expert! There is very little he doesn't know.
A:彼得真是个了不起的专家!他知识渊博。B:I have exactly the same feeling. This afternoon he explained the ins and outs of the stock market to me. He knows a lot about investments.
B：我有同感，今天下午他给我解释了股票市场的来龙去脉，他在投资方面见多识广。