` -> ` Công thức thì HTTD 

` -> ` S + be + V-ing 

` -> ` S + be not + V-ing

` -> `be + S + V-ing ?

`  -> `  DHNB : now , at the moment , at present , look ! , listen ! , ...

` -> `  VD : i am having my breakfast now

` 1 ` : are meeting

` 2 ` : are visiting

` 3 ` : isn't reading

` 4 ` : are - doing

` 5 ` isn;t listening

` 6 ` is sitting

` 7 ` : is - making ( always + V-ing : dùng để than phiền về 1 hành động của 1 ai đó )

` 8 ` are - are playing

` 9 ` : is coming

`  10 `  : isn't paniting

` 11 ` : aren't planting

` 12 ` : are - making

` 13 ` : are having

` 14 ` : is reparing

` 15 ` : is taking