Question about when to use “were” and “was”?

Question by gl9east: Question about when to use “were” and “was”?
I have 2 examples. Please let me know which ones are right
“Drinking and smoking WERE very common” OR “Drinking and smoking WAS very common”
“Music and dancing WERE popular” or “Music and dancing WAS popular”

Best answer:

Answer by Adriana
For both examples use WERE

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