My father picks my little brother up at 5 p.m every Sunday.

Công thức: S + $V_{s/es}$ 

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Look! The baby is smiling.

Công thức: S + be + V-ing

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I think he won't come to the party.

Công thức: S + will not + $V_{0}$ 

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We will bake some cakes this afternoon.

Công thức: S + will + $V_{0}$ 

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When my mother came home from work, I was cooking.

Công thức: S + be (QK) + $V_{ing}$ 

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My parents saw a snake while she was doing gardening.

Công thức: S + be (QK) + $V_{ing}$ 

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We haven't seen Tom for a long time.

Công thức: S + have/has not + $V_{3}$ 

Answer:

I

15. B to listen `->` listening

`-` enjoy + V-ing

II

1. picks

`-` every day `->` chia HTĐ

`-` S + V(s/es) + O

2. is smiling

`-` Look! `->` chia HTTD

3. won't come

`-` S + think(s) + N + will/won't + V-inf + O

4. baked

`-` this afternoon `->` chia QKD

`-` S + V-ed/V2 + O

5. was cooking

`-` When + S + V2 + O, S + was/were + V-ing + O

6. was doing

`-` While + thì QKTD

7. haven't seen

`-` for a long time `->` chia HTHT

`-` S + have/has + V3 + O