A-A+
They provide a means of keeping ______ of the
问题详情
They provide a means of keeping ______ of the thousands of journal papers that are published monthly or quarterly.
A．track
B．contact
C．relation
D．steps
参考答案
正确答案：A
解析：keep track of是一个词组，意为“跟上……，与……保持联系”。
