与…失去[保持]联系，了解[忘记]

1. 失去与...的联系,不能跟上...的进展：keep track of 与...保持联系 | lose track of 失去与...的联系,不能跟上...的进展 | make use of 利用

2. 失去...的线索：lose faith in 失去对-----的信任 | lose track of 失去----的线索 | make an appeal to sb. (for sth. ) 向某人呼吁某事

3. 与......失去联络：lose touch with 与......失去联系 | lose track of 与......失去联络 | make room for 为......腾出地方

4. 不知下落：lose one's head: 恐慌失措 | lose track of: 不知下落 | make away with: 抢走