找出不同类的单词。
(  ) 1. A. ill          B. sad       C. mouse    D. happy
(  ) 2. A. dancing        B. swimming   C. sing   D. talking
(   ) 3. A. east    B. west   C. easy   D. north
(   ) 4. A. accountant  B. artist   C. engineer  D. teach
(   ) 5. A. books   B. reads   C. teaches   D. watches