a. It seems today that the ideas of what friendship is are also changing.
b. A study in 1993 at the University of Oxford showed that people could only maintain 150 relationships.
c. There have been a lot of scientific studies into what makes a friendship.
d. Some people think that these friends are not real friends, but others believe that social media has helped us to expand and keep our fiendship becauses we have more time and opportunities.
e. However, with the explosion of social media since then, many people now have over 300 people who they think of as a friend.