单项选择题 Although the main motivation for a renewed interest in logic was a search for the foundations of mathematics, the chief protagonists of this effort extended their inquiry into the domain of the natural languages.

单项选择题 The day was crisp and sharp, but suddenly a misty rain began to fall and ______ the landscape.

单项选择题 The police inspector, having received new information from a confidential source, decided to enlarge the ______ of his enquiry.