`1.` `(-)` I am not a student.

      `(?)` Are you a student?

`2.` `(-)` He isn't hungry.

      `(?)` Is he hungry?

`3.` `(-)` She isn't happy.

      `(?)` Is she happy?

`4.` `(-)` We aren't late.

      `(?)` Are we late?

`5.` `(-)` They aren't from England.

      `(?)` Are they from England?

`6.` `(-)` It isn't very cold today.

      `(?)` Is it very cold today?

`7.` `(-)` She isn't in the livingroom.

      `(?)` Is she in the livingroom?

`8.` `(-)` We aren't playing computer games.

     `(?)` Are we playing computer games?

`->` Cấu trúc:

`+` thì Hiện tại đơn:
`-` với tobe:
`(+)` S + am/is/are

`(-)` S + am/is/are + not

`(?)` Am/Is/Are + S?

`+` thì Hiện tại tiếp diễn:

`-` với động từ thường:
`(+)` S + am/is/are + V_ing

`(?)` S + am/is/are + not + V_ing

`(?)` Am/Is/Are + S + V_ing?

`+` Chủ ngữ: I `->` tobe "am"

`+` Chủ ngữ: You/ we/ they/ N(Số nhiều) `->` tobe "are"

`+` Chủ ngữ: She/ he/ it/ N(Số ít) `->` tobe "is"