This coffee is still warm.

This algorithm was developed for optimization.

We need to optimize this process.

It is difficult to find the optimal solution to this problem.

Fuyuki likes to read books in the library every day.

Brrr! It's cold today, isn't it?

I started skiing last winter.

Let's go skiing next winter.

Let's go buy winter clothes.

This winter scenery is really beautiful, isn't it?