I don't see where "before" is in this sentence. Couldn't it be: "Have you rowed a dragon boat?"

"Have you ever rowed a dragon boat?" not accepted. Reported 23rd November 2018.

Have you ever rowed a dragon boat

Have you rowed a dragon boat

For the sticky rice dumpling -sentence it didn't suggest the "before", but for this one it was required. Consistency!

"Have you rowed a dragon boat before?", "Have you ever rowed a dragon boat?", "Have you ever rowed a dragon boat before?", "Have you paddled a dragon boat before?" etc. All of these are valid translations of the sentence and once again, we're being marked on the ability to remember a random English sentence, not on our understanding of the Chinese text.

Still has the same meaning.

Should be “Have you paddled a dragon boat before?” Rowing is when you have two oars, one in each hand. Paddling is when you grasp one oar with two hands.

This is factually wrong, dragonboats are paddled not rowed.

https://www.thoughtco.com/differences-between-rowing-and-paddling-2555860