【单选题】Three fourths of the surface of the earth ___ covered withwater.
【单选题】Three fourths of the surface of the earth ______ covered with water.
【单选题】Three fourths of the ________ in the country have run out.
【简答题】论述活性污泥法中丝状菌污泥膨胀的概念、危害和评价指标
【简答题】were/is (1)Three fourths of the teachers present _____ against the plan. (2)Three fourths of the suce of the earth ______ covered with water.
【简答题】衬叶可以修剪变曲造型吗?都有哪些形式和方法?
【单选题】Three fourths of the teachers _____ against the plan,and three fourths of the plan _____ hard for them to carry out.