Công thức thì HTTD 

(+) S + am/is/are + Ving 

(-) S + am/is/are + not + Ving 

(?) Am/Is/Are +S +Ving? 

I + am

S số ít, he, she, it + is

S số nhiều, you ,we, they + are

DHNB: now, right now, (!), at present, at the moment,.....

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2. Are you learning English? 

3. Is our teaching smiling?

4. Are we sitting next to the door?

5. Is our teacher writing on the board?

6. Is your father working in a factory now?

7. Is your mother cooking now?

`color{orange}{~MiaMB~}`