Section 3

I :

Did your experiments go well?

K :

They were not always successful. I was looking for a photocatalyst/to put in plastic water bottles. A photocatalyst was the key/to speeding up the purification process. It wasn’t easy/to find a new material for it. But I finally found one.

I :

What’s the material?

K :

It’s a mixture/of cement and a kind of metal. It’s effective/for speeding up the process. In addition,/the material is so flexible/that it can be formed/into different shapes and sizes. Without this flexibility,/it wouldn’t fit/in many different containers.

I :

In what kinds of containers/can it be used?

K :

It can be used/in not only small, personal bottles,/but also large water tanks.