阅读下面短文，根据上下文意义和所给单词首字母，写出标有题号的每小题空白处适当单词的完全、正确形式。(每空一词)

　　When I was 13 years old a boy gave me an important gift．It was a s 　　1　　 ．

　　It was the early autumn of my first year at a junior high school and my old school was far away．As a result no one k 　　2　　 who I was．I was very lonely and afraid to make friends with a 　　3　　 ．

　　Every time I heard the other students talking and l 　　4　　 I felt my heart break．I couldn’t talk to anyone about my problem and I didn’t want my parents to w 　　5　　 about me．

　　Then one day my classmates talked happily with their friends but I sat at my desk unhappily as u 　　6　　 ．At that moment a boy e 　　7　　 the classroom．I didn’t know who he was．He p 　　8　　 me and then turned back．He looked at me and without a w 　　9　　 smiled．

　　Suddenly I felt the touch of something bright and friendly．It m 　　10　　 me feel happy lively and warm．

　　That smile c 　　11　　 my life．I started to talk with the other students and made friends．

　　Day by day I became more active and c 　　12　　 to everyone in my class．The boy with the lucky smile has become my best friend now．

　　One day I asked him w 　　13　　 he smiled but he couldn’t remember smiling at me!

　　It doesn’t matter even if he didn’t tell me the reason．because all the dark days have gone．Now I believe that the world is w 　　14　　 you think it is．If you think you are lonely you might always be a 　　15　　 ．So smile at the world and it will smile back．