What I want to     to teenagers is that being addicted to the Internet will to some extent do harm to both mental and physical health．

These books are ___ children. There are many interesting stories with pictures in them.

I lost my way in complete darkness and ,______ matter worse, it began to rain.

They became good friends during the war, and since then their lifelong friendship has______ tests of life and death.

In all kinds of competitions, Jackie ______ a most excellent athlete. He has won so many golden medals.