I. Complete the sentences, using the given words in the brackets.
1. Mr. Brown wants to use solar energy. Mr. Brown does not have enough money to buy necessary equipment. (but)
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2. Shakespeare died in 1616. He had written more than 37 plays before then. (by the time)
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3. Douglas fell off his bicycle last week. He has had to use crutches to walk. (since)
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4. I turned off the lights. After that, I left the room. (before)
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5. The frying pan caught on fire. I was making dinner at that time. (while)
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6. I won’t return my book to the library. I’ll finish my research project first. (until)
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