Input: Article: Reservations are essentially caveats to a state's acceptance of a treaty. Reservations are unilateral statements purporting to exclude or to modify the legal obligation and its effects on the reserving state. These must be included at the time of signing or ratification, i.e. "a party cannot add a reservation after it has already joined a treaty".

Now answer this question: What are parties to a treaty forbidden to do after they have already joined a treaty?

Output: add a reservation

Input: Article: In league competitions, games may end in a draw. In knockout competitions where a winner is required various methods may be employed to break such a deadlock, some competitions may invoke replays. A game tied at the end of regulation time may go into extra time, which consists of two further 15-minute periods. If the score is still tied after extra time, some competitions allow the use of penalty shootouts (known officially in the Laws of the Game as "kicks from the penalty mark") to determine which team will progress to the next stage of the tournament. Goals scored during extra time periods count toward the final score of the game, but kicks from the penalty mark are only used to decide the team that progresses to the next part of the tournament (with goals scored in a penalty shootout not making up part of the final score).

Now answer this question: Which goals count to the final score of the game? 

Output: Goals scored during extra time

Input: Article: A more elaborate form of urban AC is the rhythmic oldies format, which focuses primarily on "old school" R&B and soul hits from the 1960s to the 1990s, including Motown and disco hits. The format includes soul or disco artists such as ABBA, The Village People, The Jackson 5, Donna Summer, Tina Charles, Gloria Gaynor and the Bee Gees. Rhythmic oldies stations still exist today, but target African-Americans as opposed to a mass audience.

Now answer this question: What is the earliest decade of music typically featured on the rhythmic oldies format?

Output:
1960s