4. When did you come back to Ho Chi Minh City?
5. I often play football with my friends on Sunday.
6. Last weekend my uncle stayed at my house.
7. He is wearing a T-shirt and jeans.
8. There are a lot of rivers and mountains in my country.
9. Do they usually stay in a small house or flat by the sea?
10. What do their friends like to talk about?
11. What is the season of fruits in Vietnam?
12. I often play football because it is very exciting.

Công thức: HTĐ: (+) I/ we/ you/ they + V + O.
                                 She/ he/ it + V s/es +O.
                            (-)  I / we/ you/ they + do not/ don't +V.
                                  She/ he/ it + does not/ doesn't + V.
                            (?)  (Wh-) Do/ Does + S+V+O?
Dấu hiệu nhận biết: often, usually, sometimes, always, never, once/twice/three times a week .....
                    HTTD: (+)  I + am+ V-ing.
                                     She/ he/ it + is + V-ing.
                                     We/ you/they+ are+ V-ing.
                                (-) I + am not + V-ing.
                                     She/ he/ it + is not/ isn't + V-ing.
                                     We/ you/ they + are not/ aren't + Ving.
                                (?) ( Wh-) Is/Am/Are + S+ V-ing?
Dấu hiệu nhận biết: Look! Listen! now, at present, at the moment, tomorrow, next/the following, today, this week, right now......
Công thức: QKĐ:
1. Với động từ tobe     
                                (+) I/ she/he/it + was + ....
                                      We/you/they + were + ...
                                (-)  I/she/he/it + was not/ wasn't + ....
                                      We/you/they + were not/ weren't + ...
                                (?)  (Wh-) Was/ Were + S +... ?
 2. Với động từ thường
                                (+)  S + V-ed .....
                                (-)   S + did not/ didn't + V ....
                                (?)   (Wh-) Did + S + V
Dấu hiệu nhật biết: yesterday, last night/ last week/ last month/ last year/ last Sunday... , ago....