Which sentence from a personal narrative requires a grammar revision?

a. finally, when my freckled skin started to pucker with goose bumps and my lips turned blue, we dragged ourselves out of the surf and up to shore and fell shivering on our blanket.
b. when the sun became too hot, we ran back into the crystal blue water and surf again until we are exhausted.
c. later, as brilliant oranges and pinks brushed the western sky, we gathered driftwood to build a fire and warm our chilled bones
d. the hot dogs sizzled on our broken sticks as we held them in the flames and realized we had never felt so hungry.