Sheesh, Curufin, way to point out that first fact! Sure, it's very obvious right now that Inigo is super worried, but he doesn't like letting that show. Hence why he looks slightly embarrassed when Curufin says it so easily - it makes him scratch himself behind the ears for a moment before he replies.

"Yes, I can't swim." The circumstances back home just made it really difficult to ever learn, really. He looks a tad ashamed to admit it, although he's at least being honest about it. "And.. I don't know. It sounds as if I might just waste the whole mission's worth of time if I set out to learn. I'd rather do something that was useful for other people rather than just for myself."