21. Thiếu phải là they are going to have a picnic near lake next saturday.
22. Doesn't bỏ đi vì Nam is going to bring his camera (vì các câu đều ở thì TLG thì câu này cũng vậy).
23. Bỏ not vì he is bring some drinks.
24. Thiếu là phải còn Finally, they are going to take some photos and go home.
VI)
25.is drinking(vì có at the moment dấu hiệu nhận biết thì HTTD: S+tobe+V_ing+O.)
26.are going to see(vì tonight là dự định sẽ làm gì đó dùng thì TLG: S+be going to+V_o+O).
27.going(vì sau about động từ thêm ing).
28.listening(vì sau want động từ thêm ing).

21. they are going to have a picnic near lake next saturday.
22. Nam is going to bring his camera 

Dấu hiệu tương lai 
23. he is bring some drinks.
24. Finally, they are going to take some photos and go home.
VI)
25.is drinking

Dấu hiệu hiện tại tiếp diễn sẽ có cấu trúc S + be + V-ing <--> S + am,is,are + being + V3 ( by O )
26.are going to see.

Dấu hiệu thì tương lai đơn 
27.going
28.listening

Thì HTĐ : S + V s / es <---> S + be + V3 ( by O )

- Thì QKĐ : S + V ed <---> S + was / were + V3 ( by O )

- Thì HTTD : S + be + V-ing <--> S + am,is,are + being + V3 ( by O )

- Thì QKTD : S + was / were + V-ing <---> S + was / were + being + V3 ( by O )

- Thì HTHT : S + have / has + V3 <---> S + have / has + been + V3 ( by O )

- Thì TLĐ : S + will + V <---> S + will be + V3 ( by O )