急急！！请各位帮忙！取字串问题！

var wordstr,TmpStr:string;
begin
  wordstr:=trim(edit1.Text);
  wile not （pos('',wordstr)=0） do
  begin
     TmpStr:=copy(wordstr,1,2);
     //接着用你的TmpStr去查询你数据库对应的拼音字母。
     wordstr:=copy(wordstr,2,length(wordstr));
  end;end;