GHLYS

key:
1.A Code Which Is Written In English??
 Cool！
 Let Me Tell You How To Solve It~
 Well,It's Related On A Method That Is Called Grammar.
 Someone Said That To Solve A Problem, Changes Should Be Made
 But This One Is Difficult,So Let's Use "Exchange"!
2.定语从句。
3.关系代词是用来“指代”先行词的。