to do what other people are doing or to agree with other people because it is the easiest thing to do
随大流，随波逐流

Just relax and go with the flow! 干脆放松下来，随大流吧！

There’s nothing I can do about the problem, so I might as well go with the flow. 关于这个问题我无能为力，所以我不如就顺其自然好了。

Just feel out the environment and go with the flow. 只要摸清环境，顺其自然就行。

Instead, they would rather go with the flow. 他们宁愿随大流。