The answer is B, podia.
The sentence means:
Two years ago, I couldn't swim, but now I can.
The word that best fit in the sentence was podia, which means couldn't.
Glad to help :-)
Answer:
1) Tienes que pasar la aspiradora.
2) Tienes que cuidar a la mascota.
3) Hay que lavar los platos.
4) Tienes que hablar español.
5) Hay que preparar un sándwich.
Hope this works :).
12. donde
13. quienes
14. Y
Yes, you did it correctly. Good luck on this assignment. :)