Whatever you have found，you should give it back to whomever it ________.

 Customers are asked to make sure that they______ the right change (零钱) before leaving the shop.

---Hurry, John!---Oh, damn! Both my legs are nearly to give out. I ____for hours.

 They say in many western countries a large number of beef cattle ________.

Traffic conditions in Beijing ________ for decades. At first people only complained about jams during rush hours，but today every hour is rush hour.