"To be"

Affirmative                                                     

I                am            

                                  intelligent

HE                               happy

SHE           is              19 years old

IT                               a teacher

                                   teachers

YOU                          hungry

WE            are           a Student

THEY

Interrogative

Am           I                           

                                            intelligent                   

               HE                         happy

Is           SHE                    19 years old

                IT                        a teacher                     

                                            teachers            ?

              YOU                      hungry 

Are         WE                     a Student

             THEY

Negative

I                am  not           

                                      intelligent

HE                                   happy

SHE           isn´t           19 years old

IT                                   a teacher

                                        teachers

YOU                                hungry

WE            aren´t            a Student

THEY