Yes, a former president may hold any job that he is elected to or offered. If the former president has already served 2 terms as president there are some so say he (as we have only had male presidents) is ineligable to be president but this has not be tested or tried by the courts.
you have to become a member
There is no evidence that he has ever been a member. He has given several speeches to that organization, however.
No, Barack Obama will be the first African American to become President.
Your governing documents contain the answer you seek. There is no standard.
The past participle of become is also have or has become. She has become a better person.
infinitive: become past: became past participle: become
The simple past tense is became. The past participle is become.
You don't need any specific skills to be a vice president. You should have had some history in politics and know the background of past presidents.
It is past.
"Became" is the past tense of "to become".
"Had become" is the past perfect tense of become.
The simple past tense is became. The past participle is become.