Jack crashed onto a world in the early iron age. What's worse, the natives are seven-foot-tall carnivores. So far, they've mistaken his ship for a dragon and are steering clear, but now they've left him a sacrifice, and she looks pissed. Life just got a lot more complicated...
Call Me Joe by Poul Anderson
A Voyage to Arcturus by David Lindsay
The Word for World Is Forest by Ursula K. Le Guin