“紧紧跟随”常见的英文表达有 “follow closely” 或 “keep close to”，具体使用可根据语境调整：
Follow closely：强调紧密追踪、不松懈地跟随。
例句： The detective followed the suspect closely to gather evidence.
（侦探紧紧跟随嫌疑人以收集证据。）
Keep close to：侧重于保持近距离，不远离。
例句： The children were told to keep close to their parents in the crowded market.
（孩子们被告知在拥挤的市场里要紧紧跟随父母。）
其他类似表达（根据语境选择）：
Stick with（坚持跟随/不放弃）：Stick with the plan, and we'll succeed.
Tail (someone/something)（尾随，多含跟踪意味）：The police tailed the suspect's car.
根据具体场景选择最贴切的短语即可。