The act of {verb} (to do something) is {verb} (prohibited, permitted, etc.). This sentence pattern is used to express that the action of the following verb is performed on another action.アメリカの憲法は、同じ人が大統領を3回することを禁止しています。
Verb in て-form + いますN4
Being {verb}/Being in the state of {verb}. This pattern is used to describe an action that is happening or a state that is continuing.アメリカの憲法は、同じ人が大統領を3回することを禁止しています。
Verb in て-form + ありますN4
Has already been {verb}-ed. This pattern is used to describe a state of an object that has already had an action performed on it by someone previously.帽子とTシャツには「2028」と書いてあります。