Answer:
hoisted, stumbled and last one is assisted.
Step-by-step explanation:
hoisted because looked back to see something which needs to be a thing.
stumbled over the rock which I have guessed from the preposition 'over' and have also read the context as the leg is hurt afterwards.
The last one is 'assisted' as the paramedics came to take her into ambulance. Again, I chose this one due to the context.