单项选择题
A president can serve（）term(s).
A.only one B.two C.more than two D.as many as four
单项选择题 The President of the United States is elected（）
单项选择题 The writers of the Constitution worked out the Constitution worked out the checks and balances in order to（）
单项选择题 When the delegates met at Philadelphia in 1787,their task was（）
