We need to have mentors. I think I've always been pretty shameless about seeking out people much smarter and much more experienced than me from the very beginning. Michael Seibel and other people. And the more successful I got, the more leaders I started seeking out, whether it was investors, or Sheryl Sandberg at Facebook, or I got the opportunity to spend time with Warren Buffett and he became a close mentor of mine.

Yes, in 2018, I was awarded the Breakthrough Prize for the discovery. I was a bit dumbstruck, never expecting that kind of thing to happen. I was keen that the money should be used well and the best way to do that seemed to be to encourage a more diverse research student population from under-represented groups.

Tree planting became a natural choice to address some of the initial basic needs identified by women. Also, tree planting is simple, attainable and guarantees quick, successful results within a reasonable amount time. This sustains interest and commitment.

They win the respect, the deserved trust, of the people they deal with, and there is huge pleasure in life to be obtained from getting deserved trust. And so the way to get it is to deliver what you’d want to buy if the circumstances were reversed.

I think I'm trying to be as normal as possible, as authentic as possible, and I always try to stay the same way for as long as possible,

As many of you know, the past three years have presented me with challenges in the form of injuries and surgeries. I've worked hard to return to full competitive form. But I also know my body's capacities and limits, and its message to me lately has been clear. I am 41 years old. I have played more than 1,500 matches over 24 years. Tennis has treated me more generously than I ever would have dreamt, and now I must recognize when it is time to end my competitive career.