30　课时达标训练(十八)-【提分教练】2022-2023学年新教材高中英语必修第三册(外研版2019)

课时达标训练(十八)　Period Three Ⅰ. 单句语法填空 1. If it is necessary, we will finish it ahead of time. 2. — I won't do it any more. — Why not？ 3. Although told (tell) to stop, he kept on working. 4. — Mary didn't attend the lecture, did she? — Yes, she did. 5. — What's Joan doing? — Reading (read) newspapers in the room. 6. Wood gives much smoke while burning (burn)． 7. The letter is to be left here until called (call) for. 8. It is the third time (that) I have come (come) to China. 9. Although working (work) very hard, he failed in the final exam. 10. He stood up as if to say (say) something. Ⅱ. 阅读理解 California has lost half its big trees since the 1930s, according to a study to be published Tuesday and climate change seems to be a major factor (因素). The number of trees larger than two feet across has declined by 50 percent on more than 46，000 square miles of Californian forests, the new study finds. No area was spared or unaffected, from the foggy northern coast to the Sierra Nevada Mountains to the San Gabriels above Los Angeles. In the Sierra high country (高海拔地区), the number of big trees has fallen by more than 55 percent; in parts of southern California the decline was nearly 75 percent. Many factors contributed to the decline, said Patrick McIntyre, an ecologist who was the lead author of the study. Woodcutters targeted big trees. Housing development pushed into the woods. Aggressive wildfire control has left Californian forests crowded with small trees that compete with big trees for resources (资源). But in comparing a study of Californian forests done in the 1920s and 1930s with another one between 2001 and 2010, McIntyre and his colleagues documented a widespread death of big trees that was evident even in wildland protected from woodcutting or development. The loss of big trees was greatest in areas where trees had suffered the greatest water shortage. The researchers figured out water stress with a computer model that calculated how much water trees were getti