Input: Article: After the success of quantum electrodynamics, Feynman turned to quantum gravity. By analogy with the photon, which has spin 1, he investigated the consequences of a free massless spin 2 field, and derived the Einstein field equation of general relativity, but little more. The computational device that Feynman discovered then for gravity, "ghosts", which are "particles" in the interior of his diagrams that have the "wrong" connection between spin and statistics, have proved invaluable in explaining the quantum particle behavior of the YangMills theories, for example, QCD and the electro-weak theory.

Now answer this question: Which parts of the Yang-Mills theories did Feynman help explain?

Output: QCD and the electro-weak theory

Input: Article: On 16 September 2001, at Camp David, President George W. Bush used the phrase war on terrorism in an unscripted and controversial comment when he said, "This crusade this war on terrorism is going to take a while, ... " Bush later apologized for this remark due to the negative connotations the term crusade has to people, e.g. of Muslim faith. The word crusade was not used again. On 20 September 2001, during a televised address to a joint session of congress, Bush stated that, "(o)ur 'war on terror' begins with al-Qaeda, but it does not end there. It will not end until every terrorist group of global reach has been found, stopped, and defeated."

Now answer this question: When did George W. Bush first say 'war on terrorism'?

Output: 16 September 2001

Input: Article: The word gymnastics derives from the common Greek adjective (gymnos) meaning "naked", by way of the related verb (gymnazo), whose meaning is to train naked", "train in gymnastic exercise", generally "to train, to exercise". The verb had this meaning, because athletes in ancient times exercised and competed without clothing. It came into use in the 1570s, from Latin gymnasticus, from Greek gymnastikos "fond of or skilled in bodily exercise," from gymnazein "to exercise or train" (see gymnasium).

Now answer this question: What does the verb gymnazo mean?

Output:
to train naked", "train in gymnastic exercise", generally "to train, to exercise"