Question

once vigorous ____ appear to be the only means left of bringing the __ to a due submission to the __ country, the ____ will submit. — king george iii

Explanation:

This quote from King George III relates to the American Revolution context, focusing on historical events and political relations. The subfield of History (under Social Science) is appropriate as it deals with historical statements and events, especially colonial - revolutionary era history. To fill in the blanks, the correct words (based on historical context) are: "Once vigorous measures appear to be the only means left of bringing the rebels to a due submission to the mother country, the colonies will submit."

Answer:

First blank: measures; Second blank: rebels; Third blank: mother; Fourth blank: colonies