“定时的”用英语怎么说

我所坐的这辆车恰巧是个不定时的马车.It happened to be a chance coach that I had taken up.所有需要精确定时的系统都要用晶体.All systems requiring accurate timing will require a crystal.应该鼓励员工去散步,作为他们定时的放松.Staff should be encouraged to take regular breaks t...