一个简单的背单词的功能，单词全放在 ”词汇.txt中“， 还有保存退出位置的功能，存放在“position.txt”中，进入后还能选择上次退出外置继续背单词,A simple word back function, the word on the full vocabulary txt ", as well as hold the exit location, stored in the" position.txt "enter can select the last exit t