I feel sorry for the beggars, but I can't stand it when they teach their children how to beg.
我很同情乞丐,但我真的看不惯他们教孩子怎么样行乞。
The two parties involved in a contract have the obligation to execute the contract.
合同双方有义务履行合同。
Up to now, historians have assumed that calendars came into being with the advent of agriculture, for then man was faced with a real need to understand something about the seasons.