keep track of...记录;与…保持联系; 跟踪;了解Keep track of tax-deductible expenses, such as the supplies and equipment you buy. 记下可减免课税的开支，比如买的原料和设备。Police keep track of the kidnapper using electronic surveillance equipment. 警方利用电子监视设备跟踪绑架者。With eleven thousand employees, it's very difficult to keep track of them all . 对于一支1.1万人的员工队伍，很难及时了解到所有有人的动态。She managed to keep track of her friends. 她设法与朋友们保持联系
汉朝文帝
