what are their job they're waitresses.(改为单数）

they are waitresses(改为单数 They are waitresses.(改单数句) ____ is a waitresses. 1.What are their jobs?They’re waiters.(单数) 2.What is this?It what are they doing?They 're play with yo-yos改为单数句 What colour are they?改为单数句 what are their job?are they plicemen or milken what are they?they are apples改为单数句 we are their friends (改为单数） they are very busy,what are their jobs说what is their job可以么 What coiour are the fans?they are biue.(改为单数) -What are those?-They are pencil-boxes.(改为单数句） Are they students?（改为单数句）