`1)`  is buying

`2)` is not studying

`3)` Is she running

`4)` is eating

`5)` are you waiting

`6)` are not trying

`7)` are having

`8)` are travelling

`9)` is drinking

`10)` is speaking

$--------------$

`@` Công thức

`(+)` S $+$ is / am / are $+$ Ving

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

`(?)` Is / am / are $+$ S $+$ Ving 

* He / She / It / N số ít $+$ is 

You / We / They / N số nhiều $+$ are

I $+$ am

`@` Cách dùng

`-` Diễn tả hàng động đang xảy ra

`-` Hàm mý tương lai

`@` Dấu hiệu nhận biết

`-` Now , at the moment , at presen 

`-` Thúc mệnh lệnh $($ Look $!$ , Where is mum $?$ , Listen$ ! )$