Traffic speed limits are set at a level that achieves some balance between the danger of ______ speed and the desire of most people to travel as quickly as possible.

单项选择题We must try to understand his momentary ______ for he has ______ more strain and anxiety than any among us.

单项选择题Harriman, Kennan, and Acheson were part of that inner ______ of the American diplomatic establishment whose distinguished legacy ______ U.S. foreign policy.