Grammar

   1)   Simple (Count)

The Survevor countes a building                                               (Present)

The Survevor counted a building                                               (Past)

The Survevor will count a building                                            (Future)

The Survevor would count a building                                        (Past Future)

  

   2)   Continuous (Observe)

A Supervisor is observing a dams                                              (Present)

A Supervisor was observing a dams                                          (Past)

A Supervisor will be observing a dams                                     (Future)

A Supervisor would be observing a dams                                 (Past Future)

   

   3)   Perfect (Saw)

A builder has sawn a wood                                                          (Present)

A builder had sawn a wood                                                         (Past)

A builder will have sawn a wood                                                (Future)

A builder would have sawn a wood                                            (Past Future)

  

   4)   Perfect Continuous 

The foreman has been operating a truck                                    (Present)

The foreman had been operating a truck                                   (Past)

The foreman will have been operating a truck                          (Future)

The foreman would have been operating a truck                      (Past Future)