找出下列各组中不同类的一项,将序号填在括号内。 ( )⑴A. blackboard B. window C. lunch box ( )⑵A. stand up B. sit down C. pencil case ( )⑶A. drink B. sleep C. parrot ( )⑷A. crayon B. schoolbag C. library ( )⑸A. talk B. pie C. cake ( )⑹A. open B. book C. close ( )⑺A. black B. yellow C. jacket ( )⑻A. my B. you C. your ( )⑼A. milk B. sweet C. cake ( )⑽A. look at B. good morning C. listen to