Definition: to discover more about a situation or take further action in connection with it Level: B2
如果你通过电话预订酒店，请用书面形式跟进确认。
If you make a hotel booking by phone, ___follow it ___up with something in writing.
经理承诺会立即跟进客户的投诉。
The manager promised to ___follow ___up the customer complaint immediately.
