This video is about an advance English structure "PRIOR TO" which is used for the following situation:
Ex: शादी से पहले उसका चक्कर था। 
       
        थप्पड़ मारने से पहले वह उससे बात कर रही थी। 
Structure[Sentence + prior to + noun/gerund]
      Ex: She had an affair prior to marriage.
 
              She was talking to him prior to slapping.
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