qún lǐ liáotiān hěn duō shí，shíjiān huò dìdiǎn biànhuà zuìhǎo dāndú fā yì tiáo qīngchǔ xiāoxi

群里聊天很多时，时间或地点变化最好单独发一条清楚消息。

When there's a lot of chat in the group, it's best to send a separate clear message for any change of time or location.