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Combine each pair of sentences into a complex sentence, using the given subordinator
the lights when you leave the room.
20. You set up this machine. You should read the instructions carefully.
V.
21. He could communicate his ideas clearly. His English was not good.
22. She knows the process of making pottery. She was born in Bat Trang.
23. My mother taught me to knit. I could make a scarf for my friend.
Give the correct form of the words in brackets
VL
(before)
(although)
(because)
(in order that)