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"Así que" is a phrase which is often translated as "so", and "por lo tanto" is a phrase which is often translated as "therefore". Learn more about the difference between "así que" and "por lo tanto" below.
así que()
A phrase is a group of words commonly used together (e.g., once upon a time).
a. so
Estaba muy estresado, así que decidí ir al spa para recargar las pilas.I was very stressed, so I decided to go to the spa to recharge my batteries.
por lo tanto()
A phrase is a group of words commonly used together (e.g., once upon a time).