"... Uh." Yuya's confidence comes to a halt at that, given the way Strange is bobbing up and down. He glances around for Siobhan to make sure she's still nearby. "Are you sure? Okay, I guess we can practice with swimming back to shore."

And not into deeper water, because that sounds like a complete mistake. "Swimming above water is a lot like treading, except you're going sideways," he says, and then pauses because that's kind of a horrible description. "I'll show you first!"