．Now natural disasters happen one after another, ______ warns man to treat nature kindly.

If a substance has a higher density, ____ 2, 000kg/ m³, it will not float on water.

______ with routine office tasks, she had no time tolook after her children.

In my childhood, Lily became_______ friend with me.

The moment I completed the 800­meter race in the school sports meet, my legs ________.