It's uncertain ________ the experiment is worth doing. prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace> A. if prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace> B. that C. whether D. how
【单选题】根据以下资料,回答1~4题。 In 1807 Noah Webster began his greatest work, An American Dictionary of the English Language.In preparing the work, he devoted ten years to the study of English and its relationship to ...