求翻译：合同款分三次付清,第一笔30000合同签定后一周内支付.第二笔30000合同签定后一个月内支付.第三笔50000合同签定后三个月支付.是什么意思？

Contract paid in three, one week after the first payment of 30,000 contract signed thereafter. second 30,000 paid within one month after the signing of the contract. third pen 50,000 paid three months after the signing of the contract.