1. When I meet her, I will be very glad.
2. If I meet her, I will be very glad.
3. As I meet her, I will be very glad.
4. Because I meet her, I will be very glad.
5. Because I will meet her, I will be very glad.
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Are they all grammatical?
Which one is right, #4 or #5?
Does 'As' in #3 mean 'Because' or 'When' or 'While'?
The tenses are off in #4, but the others are okay. #5 is a little strange; usually reasons come before results.
Because indicates a reason, and therefore the timing is dependent on the sense of the sentence.
When indicates a time -- also dependent on the sentence of the sentence.
While indicates a simultaneous occurrence, so the tenses need to indicate that.