why did President need to testify under oath about it?

When a grand jury is empanelled to investigate an allegation of criminal activity, anyone, absolutely anyone can be subpoenaed. A subpoena is a legal writ requiring the recipient to appear and testify. That Clinton was the President did not make him immune from that responsibility.

Thanks a lot for your reply.

whether the marriage would survive or not
There is a sentence, " the jury was really out about whether the marriage would survive," I think whether the marriage would survive or not should be decided by Clinton and his wife, not by the jury, unless either of them asked the court to decide. So I am confused.

The expression "the jury is out" means that it has not yet been decided whether something is true or not--it is a metaphor. I understand that this would confuse you. However, the use of the term "jury" in the expression "the jury is out" is metaphorical, and not literal. However, it is also true in regard to this incident that Mr. Clinton had been served a subpoena to appear before a Grand Jury investigating an allegation of criminal activity. So, the use of the term "jury" in that expression did not refer to the Grand Jury. If i have not explained this to your satisfaction, please let me know, and i'll try to explain it again in a manner which will make it clear to you.

divorce or not
It seems that the passage does not mean that either of the couple wanted to divorce, he or she did not ask the court to decide it. There is no need for the jury to decide it. Is that right?

Re: divorce or not


The passage does not contain a conclusion about whether or not the couple wanted to divorce, which is why the idiomatic expression "the jury is out" was used--because it was not yet determined. The Grand Jury before which Mr. Clinton was subpoenaed to testify was not concerned with the issue of whether or not the Clintons should divorce. What i am trying to get across to you is that there was a Grand Jury before which Mr. Clinton was obliged to testify; the expression "the jury is out" is only a metaphor, and does not refer to an actual jury, does not refer to any court action, and does not refer to the Grand Jury which had subpoenaed Mr. Clinton to testify.

I got it. Thank you very much for your reply. You are so kind, helpful.

Well, i hope it did help. It was very confusing for someone who is not familiar with that expression, and i would not have seen that myself if you had not asked your question.

You're new around here, aren't you?