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.

去年我开始拍摄很多黑白照片，我想跟进整个流程，所以买了一台放大机和所有配套设备。

Last year I started to take a lot of black and white photos and I wanted to ___follow ___up the process so I bought an enlarger with all the equipment to go with it.

经理承诺会立即跟进客户的投诉。

The manager promised to ___follow ___up the customer complaint immediately.