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Practice(luyện tập.)
1.We can't see the stars at night because there is too much light
pollution.(so)
2. Plants can't grow ,because the soil is polluted .(so)
3. Because his room is untidy, his mother is unhappy.(so)
4. Because it rained heavily, the road in front of my house was
flooded. (so)
5. Vy had a stomachache because she ate a big dinner.(so)
6. Vy had a stomachache because she ate a big dinner.(since)