One day we will manage to ______ the world ______ this terrible disease—cancer.

I heard the clock _________eight when I woke up this morning.

In our school students are ________ according to how much they know and how old they are.

In that big earthquake all their houses were         , so they had to build new ones.

Nowadays many women are _____ their late twenties or early thirties when they have their first child.