Bad habits do not come suddenly．They come little by little while people do not notice their ___1___．Schoolboys first pick up little bad habits in schools and in the streets．When they can't finish their ___2___，they copy from their classmates．If they see bigger boys smoking，they also want to learn to smoke．When they ___3___ bigger，their habits become so strong that they can no longer get rid of the them．From copying，they fall behind，then learn to steal，and smoking is ___4___ for their bodies．At last they become worse and worse．___5___ necessary it is that we get rid of the bad habits in the beginning!

1．A．danger                   B．dangerous            C．in danger

2．A．book                     B．job                      C．homework

3．A．grow                     B．find                     C．see

4．A．helpful            B．bad                      C．hard

5．A．How                     B．What                   C．What a