I can not
Please could someone explain the difference between 'je n'arrive pas' and 'je ne peux pas' to say 'I can not'? I found 'je n'arrive pas à avaler' used in an exercise to say 'I can't swallow' and I don't understand why this is used instead of 'je ne peux pas à avaler'.
You will hear « je n'arrive pas » all the time. The difference is small, but it tends to mean you have tried a lot... and regardless of your efforts, you still don't manage to swallow. For example, I might say « je ne peux pas voler un avion », but I wouldn't say « je n'arrive pas à voler un avion », because I've never tried it, and never will either. If I had tried a lot, then I might say it. Then there's a third way: « je ne sais pas voler un avion », which is ''I don't know how to fly an aeroplane''... in this case, probably even more appropriate. There might be a better word than voler in this sentence, but I can't think of it at this moment.