Nelson Mandela was a figure of international fame, and many details of his life and career were public knowledge. But here are four things you may not have known about the late South African leader.
1. He was a boxing fan.
In his youth, Nelson Mandela enjoyed boxing and long-distance running. Even during the 27 years he spent in prison, he would exercise every morning. "I did not enjoy the violence of boxing so much as the science of it. I was curious by how one moved one's body to protect oneself, how one used a strategy both to attack and retreat, how one paced oneself over a match," he wrote in his autobiography Long Walk to Freedom.
2. His original name was not Nelson.
Rolihlahla Mandela was nine years old when a teacher at the primary Methodist school where he was studying in Qunu, South Africa, gave him an English name “Nelson” in accordance with the custom to give all school children Christian names.
3. He forgot his glasses when he was released from prison.
Mr. Mandela's release on 11 February 1990 followed years of political pressure against apartheid(种族隔离). Mr. Mandela's reading glasses stayed behind in prison.  Mr. Mandela and his then-wife Winnie were taken to the centre of Cape Town to address a huge and exciting crowd. But when he pulled out the text of his speech, he realized he had forgotten his glasses and had to borrow Winnie's.
4. He had his own law firm, but it took him years to get a law degree.
Mr. Mandela studied law on and off for 50 years from 1939, failing about half the courses he took. A two-year diploma(学位证书) in law on top of his university degree allowed him to practice, and in August 1952, he and Oliver Tambo set up South Africa's first black law firm, Mandela and Tambo, in Johannesburg. He kept on studying hard to finally secure a law degree while in prison in 1989.
What is the main idea of the passage?

A．Nelson Mandela’s life in the prison.

B．Unknown things about Nelson Mandela.

C．Nelson Mandela’s hobbies and career.

D．The achievements of Nelson Mandela.

Why did Nelson Mandela love boxing?

A．Because he wanted to be a boxer.

B．Because he loved the science in boxing.

C．Because he enjoyed the violence of boxing.

D．Because he had nothing else to do in the prison.

What happened to Mandela when he was about to give the speech?

A．He broke his glasses into pieces.

B．He left his own glasses at home.

C．He had to use his wife’s glasses.

D．His wife wanted to borrow his glasses.

Which of the following is NOT true according to the passage?

A．Nelson Mandela was not his original name.

B．Nelson Mandela was the name given by his teacher.

C．Nelson Mandela had started his own law firm before he got a law degree.

D．Nelson Mandela had been studying the law nonstop for 50 years.