1. Come came come Go went goneDo did done Understand understood understood Fly flew flown Bring brought brought Think thought thought Be was/were been Leave left left Get got gotSing sang sung Eat ate eaten Write wrote written Play played played Drop dropped dropped 2. has sung have sung has sung has sunghas sunghave sung have sung have sung 3. Have you aver been Have you red Have you lived Have you beenWhat's the most beautiful country thAt you have ever visited4. have just had have just seenhas already left haven't red yet has already seen have just arrived