提醒‘ora-00933sql命令未正确结束’

提示‘ora-00933sql命令未正确结束’
  sqlstr:='update T_LH_Bonus_department set sign=1,COMMIT_DATA=sysdate,COMMIT_USER=1234 where '
                          +'Bonus_Year ='
                          + QuotedStr(edtYear.text)
                          +'and'
                          +'Bonus_month='
                          + QuotedStr(edtMonth.text);


求解答啊 我反反复复找了一个多小时 也在sqlplus里面试过了 sql语句没错啊。
SQL

------解决方案--------------------
+'and' 
and前后加空格

+' and  '