Unfortunately, the element Madam Curie devoted all her life              her death.

We still remember once__________round the famous tower when we were young.

He said while ______ in the countryside, he ______ a lot of hardships and of course learned a lot.

The classroom with windows_____ north wants_______ badly, so we’d better move the students into the classroom next door. 

________ with some research materials, he decided on three possible approaches in his experiment.