DIFFERENCE BETWEEN AFTER AND AFTERWARDS:

The English word ‘after’ is used in the sense of ‘when something or someone has happened or will happen’ as in the sentences:
1. They will arrive after 18h.
2. She will get his chance after Melanie gets her opportunity.

In both sentences you can find that the word ‘after’ is used in the sense of ‘when something has happened or will happen or if someone has done or will do something’ and thus the meaning of the first sentence would be ‘They will arrive once 18h will happen/has happened’. The meaning of the second sentence could be ‘she will get his chance once Melanie’s opportunity has happened’.
However, the word ‘afterwards’ means ‘after that’ or ‘after something happens’ but it is used when no object follows. For example:
1. The concert finishes at 17h. I will arrive afterwards (after that/after ‘the concert’ happens).
2. She forgot to arrive on time. She made an apology afterwards (after that/after ‘her unpunctuality’ happens).
Remember that ‘afterwards’ cannot take an object, ever! So we cannot say ‘I will see you afterwards the concert’ or ‘she will have lunch afterwards giving the speech’. In these cases we’d use ‘after’, thus:
‘I will see you after the concert’ or ‘she will have lunch after giving the speech’.
Unfortunately, with native speakers, there is no doubt that many speakers readily also use after without an object too. So some people will say ‘I will arrive after’ or ‘she made an apology after’. We would say that it’s more correct to use ‘afterwards’ here.
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