Pak Rahmansyah: When I ______ your age, I often ____ down to this river.
Galang: But, it does not look very clean. Was the river this dirty back then? Did you swim in the river?
Pak Rahmansyah: I did! The river ______ quite clean back then.
Galang: Were there many children in the river?
Pak Rahmansyah: A lot of kids _______ and ______ in the river.
Galang: How did it become so dirty like this? Did people throw their trash into this river?
Bu Posma: Well, that is one of the causes. People also ________ to use a lot of plastic. And plastic does not decay easily.
Pak Rahmansyah: Plastic trash _____ to litter a lot of places. It ______ this river dirty.
Bu Posma: The plastic trash also ______ many other problems, like the flood in a nearby town a couple of days ago.
Read the dialogue. Choose the correct answer.