1. they had built this house since 1950
-> this house had been built since 1950
2. If she dosen't work hard , she will not pass the exam
-> unless she works hard, she will not pass the exam
3. Tung ate a lot last night , so he had a stomachache
->Because Tung ate a lot last night, he had a stomachache
4. My mother had gone to work before I gop up
-> After my mother had gone to work, I got up
5. I took a shower then I washed the clothes
-> Before I washed the clothes, I had taken a shower
1. They had built this house since 1950
-> this house HAD BEEN BUILT SINCE 1950
2. If she doesn't work hard , she will not pass the exam
-> unless SHE WORKS HARD,SHE WILL PASS THE EXAM
3. Tung ate a lot las tnight , so he had a stomache
->Because TUNG ATE A LOT LAST NIGHT,HE HAD A STOMACHE
4. My mother had gone tho work before I gop up
-> After MY MOTHER HAD GONE THE WORK,SHE GOT UP
5. I took a shower then I washed the clothes
-> Before I TOOK A SHOWER,I WASHED THE CLOTHES