text='Hello World'; x='World'; y='Universe'; y_correct = 'Hello Universe'; assert(isequal(Replace(text,x,y),y_correct))

text='A woman is in the Bahamas. She visits a dolphin encounter. She drops her phone in the water. A dolphin finds the phone. It brings it back to the woman. Unfortunately, the phone is already dead. Difficult words: dolphin encounter (when you get to visit a dolphin), drop (to let something fall by accident), unfortunately (sadly).' x='dolphin'; y='whale'; y_correct = 'A woman is in the Bahamas. She visits a whale encounter. She drops her phone in the water. A whale finds the phone. It brings it back to the woman. Unfortunately, the phone is already dead. Difficult words: whale encounter (when you get to visit a whale), drop (to let something fall by accident), unfortunately (sadly).'; assert(isequal(Replace(text,x,y),y_correct))