At the Science Museum Yesterday, I saw a (22) (child/children) looking at a display about (23) (bacteria/bacterium). She asked the guide, “Are all bacteria bad?” The (24) (man/men) smiled and said, “No, some bacteria help (25) (person/people) stay healthy.” In another room, I saw a (26) (mouse/mice) running across the floor, and then two (27) (mouse/mice) near a glass case. A (28) (woman/women) next to me said, “Wow, they look real!”