Jet lag is caused because the body clock does not readjust immediately to the time change.由于人体生物钟不能迅速对时差作出调整，因而产生了飞机时差反应。Are you over your jet lag yet?你是否克服了时差综合症?But I rarely have a huge problem with jet lag.但是我很少在时差方面有...
我们将研究称为收敛数列的很特别的一类数列.We shall study a very particular kind of sequences, called convergent sequences.数据数列是表达资料的一种最简单的方法.The data array is one of the simplest ways to present data.这些综合指数是使通过把它们的组成部分中的各个数列标准化而获得的.These com...