?
查询技巧:
1、输入单个单词准确查询。
2、使用%模糊查询,匹配任意长度字符:
   %a    以a结尾的单词;
   ab%    以ab开头的单词;
   %ac%    含有ac的单词。
3、使用_模糊查询,匹配单个任意字符:
   _a_    三位且a在中间的单词;
   _ad    三位且ad结尾的单词;
   ac_    三位且ac开头的单词;
   _a    两位且a结尾的单词;
   a_    两位且a开头的单词。
4、带连字符-的单词,需含-字符才能模糊查询,如well-know需输入 well-% 。
5、在手机键盘上,如果g上有%和v上有_,则可长按输入。

which
初中

英 / wɪtʃ /
美 / wɪtʃ /
pron. 哪个;那;哪一个;…的那些

1. They all look so alike to me that I'm never sure which is which.
它们在我看来简直一模一样,我永远分不清哪个是哪个。
2. It was difficult for the inspectors to discover which documents were important and which were not.
检查员们难以发现哪些文件重要,哪些不重要。
3. Which direction are you facing?
你面朝哪个方向?
4. Which planets can sustain life?
哪些行星可以维持生命的存在?
5. Which way is the wind blowing?
风朝哪个方向刮?