Answer:
The sentence is:
Enrique knocked down his sister's dollhouse
here the action is "Knocked" or "knocked down", and the verb, in Spanish, is "Derribar" or "Tirar".
If we want to write this in a preterite tense, we need to use the perfect preterite, because the action has already ben ended (the house is already ben knocked down) so the two ways os say this is:
Enrique derribó la casa de muñecas de su hermana.
Enrique tiró abajo la casa de muñecas de su hermana.