Công thức thì HTHT

(+) S + has/have + V3/ed 

(-) S + has/have + not + V3/ed 

(?) Has/Have + S+ V3/ed?

DHNB: before, since + mốc thời gian, for + khoảng thời gian, yet, already, just,....

Công thức thì HTTD 

(+) S + am/is/are + Ving 

(-) S + am/is/are + not + Ving 

(?) Am/Is/Are +S +Ving? 

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

Công thức thì HTĐ (V: thường)

S số ít, he, she, it 

(+) S + Vs/es

(-) S+ doesn't + V1 

(?) Does +S +V1?

S số nhiều, I, you, we, they

(+) S + V1 

(-) S+ don't + V1 

(?) Do + S+ V1? 

DHNB: always, usually, sometimes, often, never, seldom

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II)

1. have you studied

DHNB: for 5 years (HTHT)

2. have been waiting / hasn't come

DHNB: for two hours (HTHTTD/ HTHT) - yet (HTHT)

3. have lived

DHNB: since 1975 (HTHT)

4. has read / have / read

5. hasn't been / has lived

DHNB: since (HTHT)

6. has gone / has never been

DHNB: never (HTHT)

7. Have you been sleeping / have been ringing

DHNB: so far (HTHT / HTHTTD)

8. has been writing / hasn't finished

DHNB: for two years (HTHT/HTHTTD) , yet (HTHT)

9. has lost / has been looking

10. have seen

III)

1. think / is knocking

DHNMB: Listen! (HTTD)

2. have been writing

DHNB: up to the present (HTHTTD)

3. circles

DHNB: every 365 days (HTD)

4. are working

DHNB: at the moment (HTTD)

5. have you seen

IV.

1. practises 

DHNB: every day (HTD)

`color{orange}{~LeAiFuRuiHuiBao~}`