This word commonly refers to time, helping us to explain the order in which events happen:
She went back to work very quickly after her operation.
It can also sometimes refer to space, usually helping place people or things in order:
‘Where are you going?’ said Lee, coming after him.
After can be:
 a PREPOSITION:
After his election Dr Kumar spoke of the racial attacks he endured during the campaign.
 a SUBORDINATING CONJUNCTION:
After he was elected in November, he revealed that he had been the subject of racial attacks during his campaign.
 an ADVERB:
Then he spun around and strode out of the door, his men following after without a word.
It is also used to MODIFY a NOUN in phrase such as the morning after.
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