基本信息
unit 4 astronomy: the science of the stars ⅰ.语法单句填空 1．________existed a certain doubt among the workers as to the necessity of the work. 答案： there 句意为：对于做这份工作的必要性，工人们存在一定的疑惑。there exists/existed...有；存在；相当于there be...结构。 2．the transformation of our city will make ________ possible for people here to have a comfortable environme
