Vivianhasfinishedherhomework.

　　Thechildrenhaveplayedwiththeirtoys.

　　Ihavecleanedtheshoes.

　　IhavebeentoDisneyland.

　　Haveyouarguedwithyourfriend?

　　Haveyoutraveledtoanotherplace?

　　Shehasnotgonehome.

　　Hehaseattenlunce.

　　Theyhavebeenawayforthreeyears.

　　wehaveknowneachotherformorethan20years.

　　Theflowersshouldbewateredeveryday.

　　Carsmustn'tbeparkedhere.

　　ChildrencanbetakentothecinemafreeonChildren'sDay.

　　Teenagersshouldbeallowedtogooutwiththeirfriends.

　　Manytreesshouldbeplantedonthemountains.

　　youngtreesmustbewateredoften.

　　yourmistakesshouldbecorrectedrightnow.

　　theobjectsinthefilmcanbetouched.

　　specialglovesmustbewron.

　　Tablescanbemadeofstone.