32个关键字：（由系统定义，不能重作其它定义） auto break case char const continue default do double else enum extern float for goto f int long register return short signed sizeof static struct switch typedef unsigned union void volatile while
32个关键字：(由系统定义，不能重作其它定义) auto break case char const continue default do double else enum extern float for goto if int long register return short signed sizeof static struct switch typedef unsigned union void volatile while <
9种控制语句： if()~else~ for() while()~ do~while() continue break switch goto return
9种控制语句： if( )~else~ for( )~ while( )~ do~while( ) continue break switch goto return <