Lucy is on duty today.Look!She is c______ the blackboard 问:空

Lucy is on duty today.Look!She is c______ the blackboard 问:空 Tim is on duty today.Look!He _____ [clean]the blackboard. is on duty today what is on duty today? who is on duty today Look.Lucy is____a new red dress.She is beautiful today. Look!The girl is __________(确实) writing on the blackboard. Today is my on duty for the day. Who is on duty today?为什么用on duty Is she _____ duty today?填介词, Who is on duty today ?是什么意思 谢谢 whose turn is it ( ) on duty today