"I help the kid swim."
Translation:Tôi giúp đỡ đứa trẻ bơi.
Okay. So, why giúp đỡ accepted sometimes and not other times. According to the lesson notes when it's "help + somebody" it should just be giúp. But that doesn't match this sentence.
bơi and lội mean the same thing, just different dialects. Together they form "bơi lội" meaning "swimming".
When would you use "phụ" vs. "giúp"? I used phụ and was marked incorrect.