China has thousands of islands, the largest ___ is Taiwan.
The student became ______ the danger of smoking and decided to give it up.
The police are looking for a missing boy, who is believed _______ a white pullover and a blue jeans.
----Have you seen _____ pen? I left it here this morning. ----Is it ____ black one? I think I saw it somewhere.
-- Would you help sweep the floor? -- _____ I’d rather water the flowers.
-- Come on, please give me some ideas about the project. -- sorry, with so much work _____ my mind, I almost break down.