1) Count (simple)  

- The survevor count a building (present tense) 

- The survevor counted a building ( Past Tense)     

- The survevor will count a building (Future Tense)     

- The survevor would count a building ( Past Future Tense)

2) Observe ( Continuous) 

- The supervisor is observing a dams      

- The supervisor was observing a dams     

- The supervisor will be observing a dams      

- The supervisor would be observing a dams 

3) Saw (Perfect)     

- Builder has sawed a wood     

- Builder has saw a wood     

- The builder will have saw a wood     

- The builder would have saw a wood

4) Operate (Perfect Continuous)     

- The foreman has been operating a truck     

- The foreman had been operating a truck     

- The foreman will have been operating a truck     

- The foreman would have been operating a truck