Answer:
The correct answer to the question: Which sentence is constructed correctly and clearly, from the options, would be: "Because we wanted at long last to be finished with the project, we forgot the conclusion."
Explanation:
The reason for this lies in the correct use of grammatical structure, and the correct organization of ideas. In the first option, the removal of the preposition to, and then adding the phrase "at long last", takes away the need to use any punctuation, which should be present in the second option. In the second option, a comma becomes necessary because the use of "at long last" after to, transforms it into added information. However, what the sentence wants is to underline that the reason why they forgot to place the conclusion is because they were in a hurry to finish, a fact that is made clear by the use of "at long last". The first sentence is the one that shows this urgency as a vital part of the information, organizes the information correctly, and uses grammatical structure correctly.
