differences between start up and start off

hi every one
I have looked the meaning of start up and start off in the dictionary. but I still cant get their differences. would you please tell me what do they mean exactly? whats the difference in meaning when you say: " start up the argument" and " start off the argument".
thanks for your times in advance

Hi Farnaz,

Both suggest ‘begin again’. ‘Start up’ suggests begin possibly for the second time or more and ‘start off’ gives the idea that you begin something again almost in opposition to what others want.

Alan

Hi Alan,
So many thanks. Now I know when to use each of them.