Ⅰ.单句语法填空：根据句意，在空线处填上适当的连词。
1．(2019·湖南省三湘名校教育联盟高三第一次大联考)Professor Hawking even went so far as to say that AI may replace humans altogether, ________ he didn't state exactly a timeline for his forecast.
答案：but 句意：……但是，他没有准确地说明他所预测的时间表。表示转折关系，所以填but。
2．(2019·黑龙江哈尔滨三中高三第二次调研)Adversity (逆境) can beat you down, ________ probably it also has the ability to make you stronger.
答案：but/yet 句意：逆境可能会打倒你，但是也可能会让你变得更强。前后句表示转折关系，所以填but/yet。
3．(2019·陕西省咸阳市高三模拟检测)It is not ________ you experience in person that you can get the real meaning from nature.
答案：until 强调“直到……才”，用not until，故填until。
4．(2019·陕西咸阳市高三模拟检测)The excitement is building in Salzburg (Festival) both for this summer ________ for its 100th anniversary year in 2020.
答案：and both ... and ... “既……又……”，并列连词词组，连接两个对等的成分。
