quota
/ˈkwəutə; `kwotə/ n
1 fixed share that must be done or contributed or received 定额; 限额; 配额
have one's full quota of rations 有自己全份的配给量
I'm going home now I've done my quota of work for the day. 我现在回家了--我已经完成了今天的工作定额.
2 maximum number or amount of people or things allowed, eg to enter a country （人或事物的）最高限额（如准予入境者）
Grain imports are controlled by strict quotas. 谷物进口量受最高限额的严格控制.