Write full negative sentences. Don’t use short forms and full stops (they are given).

1. They have visited the Colosseum.​

They haven't visited the Colosseum.

To write a full negative sentence without using short forms and full stops, we need to use the word "not" after the auxiliary verb. In this case, the auxiliary verb is "have" because "have" is used for the present perfect tense. Here is the step-by-step solution:

Step 1: Start with the affirmative sentence:
"They have visited the Colosseum."

Step 2: Identify the auxiliary verb:
In this sentence, the auxiliary verb is "have."

Step 3: Place "not" after the auxiliary verb:
"They have not visited the Colosseum."

Step 4: Add a full stop at the end of the sentence:
"They have not visited the Colosseum."

Explanation: By adding "not" after the auxiliary verb "have," we negate the meaning of the sentence. It indicates that the action of visiting the Colosseum has not taken place. The full stop at the end of the sentence indicates the end of the statement.

Please note that the use of "not" is essential to form a negative sentence, and the full stop is necessary to mark the end of the sentence.