Раскрыть скобки и указать форму страдательного залога I live in a very old town which fto Indennite Passive) by surround

I live in a very old town which is surrounded (Present Indennite Passive) by beauty woods. On Sundays many people walk in the woods. Visitors have been asked (Present Perfect Passive) to keep the woods clean. Litter baskets have been placed (Present Perfect Passive) under the trees. Yesterday I went to the woods. What I saw there made me sad. The liner baskets were empty and the ground was covered (Past Indefinite Passive) with pieces of paper and cans. Among the paper and rubbish I found a sign which said who litter in the woods will be prosecuted (Future Indefinite Passive).