Welcome to Sunday! The five stories that got the most traffic on our site this week are displayed below.

Read about how one scholar collected 20,301 tweets to analyze how Trump used the social media platform to tell his own story or how infrastructure built by enslaved people is creating wealth in America today.

Deep dive: Of course, today is Valentine’s Day. If you’re curious about the origins of this holiday celebrating love, you’ll want to read this 2018 article written by Lisa Bitel, a professor of history and religion at USC Dornsife. Bitel dug into the 68-volume “Life of the Saints” – a history researched and published by a sect of Jesuit monks over 300 years – to tell us more about “Valentini.” That’s right, there was more than one St. Valentine – and none of them lived lives filled with flowers and chocolate.

Emily Costello

Deputy Editor

President Donald Trump uses his smartphone. AP Photo/Alex Brandon

I analyzed all of Trump’s tweets to find out what he was really saying

Michael Humphrey, Colorado State University

The 45th president of the United States used a specific technique to tell different versions of the very same story, of a nation under threat and a man working to save it.

Signs of a fraying relationship can appear in subtle ways. Betsie Van der Meer via Getty Images

Evidence of an impending breakup may exist in everyday conversation – months before either partner realizes their relationship is tanking

Sarah Seraj, The University of Texas at Austin College of Liberal Arts; James W. Pennebaker, The University of Texas at Austin College of Liberal Arts; Kate G. Blackburn, The University of Texas at Austin College of Liberal Arts

Psycholinguistic researchers analyzed more than 1 million Reddit posts a year before and a year after users posted about their breakup.