Sample 1: Regular verb "Change", Subject: It

Tense                     :Positive                   ;Question                   ;Negative
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Present         Simple    :It changes.                ;Does it change?            ;It doesn't change.
Present         Continuous:It is changing.            ;Is it changing?            ;It isn't changing.
Present Perfect Simple    :It has changed.            ;Has it changed?            ;It hasn't changed.
Present Perfect Continuous:It has been changing.      ;Has it been changing?      ;It hasn't been changing.
Past            Simple    :It changed.                ;Did it change?             ;It didn't change.
Past            Continuous:It was changing.           ;Was it changing?           ;It wasn't changing.
Past    Perfect Simple    :It had changed.            ;Had it changed?            ;It hadn't changed.
Past    Perfect Continuous:It had been changing.      ;Had it been changing?      ;It hadn't been changing.
Future          Simple    :It will change.            ;Will it change?            ;It won't change.
Future          Continuous:It will be changing.       ;Will it be changing?       ;It won't be changing.
Future  Perfect Simple    :It will have changed.      ;Will it have changed?      ;It won't have changed.
Future  Perfect Continuous:It will have been changing.;Will it have been changing?;It won't have been changing.


Sample 2: Irregular verb "Write", Subject: We

Tense                     :Positive                   ;Question                   ;Negative
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Present         Simple    :We write.                  ;Do we write?               ;We don't write.
Present         Continuous:We are writing.            ;Are we writing?            ;We aren't writing.
Present Perfect Simple    :We have written.           ;Have we written?           ;We haven't written.
Present Perfect Continuous:We have been writing.      ;Have we been writing?      ;We haven't been writing.
Past            Simple    :We wrote.                  ;Did we write?              ;We didn't write.
Past            Continuous:We were writing.           ;Were we writing?           ;We weren't writing.
Past    Perfect Simple    :We had written.            ;Had we written?            ;We hadn't written.
Past    Perfect Continuous:We had been writing.       ;Had we been writing?       ;We hadn't been writing.
Future          Simple    :We will write.             ;Will we write?             ;We won't write.
Future          Continuous:We will be writing.        ;Will we be writing?        ;We won't be writing.
Future  Perfect Simple    :We will have written.      ;Will we have written?      ;We won't have written.
Future  Perfect Continuous:We will have been writing. ;Will we have been writing? ;We won't have been writing.


Sample 3: Irregular verb "Eat", Subject: I

Tense                     :Positive                   ;Question                   ;Negative
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Present         Simple    :I eat.                     ;Do I eat?                  ;I don't eat.
Present         Continuous:I am eating.               ;Am I eating?               ;I'm not eating.
Present Perfect Simple    :I have eaten.              ;Have I eaten?              ;I haven't eaten.
Present Perfect Continuous:I have been eating.        ;Have I been eating?        ;I haven't been eating.
Past            Simple    :I ate.                     ;Did I eat?                 ;I didn't eat.
Past            Continuous:I was eating.              ;Was I eating?              ;I wasn't eating.
Past    Perfect Simple    :I had eaten.               ;Had I eaten?               ;I hadn't eaten.
Past    Perfect Continuous:I had been eating.         ;Had I been eating?         ;I hadn't been eating.
Future          Simple    :I will eat.                ;Will I eat?                ;I won't eat.
Future          Continuous:I will be eating.          ;Will I be eating?          ;I won't be eating.
Future  Perfect Simple    :I will have eaten.         ;Will I have eaten?         ;I won't have eaten.
Future  Perfect Continuous:I will have been eating.   ;Will I have been eating?   ;I won't have been eating.