After + S+ had + P(II), S + V_ quá khứ

before S + V_quá khứ, S + had P(II)
2. After her children had left home, she started writing

Before she started writing, her children had left home

3. After Julia had cleaned the house, she felt asleep on the sofa

Before Julia felt asleep on the sofa, she had cleaned the house

4. After we had had dinner, we went to the concert

Before we went to the concert, we had had dinner

5. Before he went to sleep, he had finished reading his book

After he had fisnish reading his book, he went to sleep

6. After peter had answered the phone, he went out

before Peter went out, he had answered the phone

7. After I had considered what to study, I decided to major in Math

Before I decided to major in Math, I had considered what to study

8. After he had checked the prices, he bought a  cassette

Before he bought a cassette, he had checked the prices

9.  After she had taken some medicine, she felt a little better

before she felt a little better, she had taken some medicines

10. After she had left the house, I arrived there

before I arrived there, she had left the house