Since, from

Words that indicate that something will start to happen at some time and continue for some time.

• What words indicate that something starts to happen after a particular time and then continues?
  starting from as from after that
• What words indicate that something started in the past and continued until now?
  since ever since for from starting from from that time on thereafter
• What words indicate that something starts to happen now and will continue?
  from now on from this time forward starting now starting from now effective immediately henceforth
• What words indicate that something will start in the future and continue?
  from then on starting then