in a way that does not happen regularly or continuously; in a way that stops and starts repeatedly or with periods in between

We've discussed this problem intermittently, but so far we've failed to come up with a solution. 我们断断续续地讨论过这个问题，但目前还没有找到解决方案。

Lightning flashed intermittently in an otherwise clear sky. 闪电在原本晴朗的天空中断断续续地闪现。