I was wondering : are “after” and “before” prepositions or adverbs? You can’t say “I have dinner, and after I watch TV”, can you?
They can act both as adverbs AND prepositions.
Before a noun, they’re prepositions:
- I went to work after breakfast.
- Sales went up before Christmas.
When not followed by nouns, they’re adverbs:
- She met me the day after.
- I hadn’t slept the night before.
You’re right when you say that “I have dinner, and after I watch TV.” is NOT correct.
’After’ acts as a preposition here, so it should be followed by a noun:
- “I have dinner, and after that I watch TV .”
