The fourth and potentially most significant day of public impeachment hearings is about to begin.

Gordon Sondland, U.S. ambassador to the European Union, will testify before Congress on Wednesday as part of the ongoing impeachment inquiry into President Trump, which focuses on whether Trump improperly pressured Ukraine to open investigations that might benefit him politically, including by withholding military aid.

Earlier this month, Sondland revised his earlier closed-door testimony to admit he told Ukraine aid to the country that was being held up would likely not be released "until Ukraine provided the public anticorruption statement that we had been discussing for many weeks," The New York Times reports. As to why Sondland didn't mention this when he originally testified and said that he didn't "recall taking part in any effort to encourage an investigation into the Bidens," he said he had since had his recollection "refreshed."

Of all the witnesses who have testified in the public impeachment hearings so far, The New York Times reports Sondland is the one who people close to Trump are most concerned about, as they have expressed "worry that he interacted directly with the president about Ukraine and that they do not know what he will say." The Times notes Sondland is also likely to face questions about why he didn't disclose a phone call he had with Trump about "the investigations" on July 26, which was first revealed during the public testimony of William Taylor, acting ambassador to Ukraine.

The Sondland hearing is scheduled to get underway at 9:00 a.m. Eastern. Also set to testify on Wednesday are Pentagon official Laura Cooper and State Department official David Hale. The impeachment hearing can be streamed below via PBS. Brendan Morrow

John Prine, who died this week from complications of COVID-19, left the world a catalog of great songs and a legion of fans who revere them. His death during an unprecedented time of mass self-quarantine also shaped the tributes — a singer and an instrument. Among Prine's ardent admirers is Stephen Colbert. He asked Brandi Carlile to sing one of Prine's songs on Wednesday's Late Show, and Dave Matthews continued the tribute on Thursday. Watch him perform Prine's elegiac "Speed of the Sound of Loneliness," alone at his house, below. Peter Weber

To limit the spread of the COVID-19 coronavirus, the Centers for Disease Control and Prevention (CDC) started advising last week that Americans wear face masks in public in areas where they can't keep a safe six-foot distance from people. But U.S. health officials don't want people buying masks — the limited supply is needed in hospitals dealing with the pandemic.

Not everyone knows how to make a mask at home, though, and in a CNN town hall Thursday night, Dr. Sanjay Gupta demonstrated some options, including creating a mask from a bandana and large hair bands. Dr. Celine Gounder fielded a question on how to safely use and sanitize your homemade cloth mask: remove the mask from behind your ears, then throw it in the washing machine and wash your hands.

Surgeon General Jerome Adams also demonstrated how to make a mask using two rubber bands and a cut-up T-shirt, though a bandana, hand towel, tea towel, or old scarf would also work.

Researchers suggest using tighter-knit fabrics — hold it up to the light to get a sense of the density of the weave — but say any fabric is better than none. You don't need to wear the mask when you go for a walk outside by yourself, Gupta said, but when you can't social-distance, the mask can help prevent you from spreading the virus to others, as their masks protect you. "Everyone has to behave like they have the virus," he said. Peter Weber

The Health and Human Services Department announced Thursday evening that it will no longer end support for community-based COVID-19 coronavirus testing sites on Friday, as originally planned. "The federal government is not abandoning any of the community-based test sites," Adm. Brett Giroir, assistant secretary for health told reporters over the phone. "I want that to be loud and clear." Instead, the local authorities hosting the testing sites can decide whether to shift to running the program themselves, as HHS had envisioned, or continue getting federal assistance.

After a late, botched start, U.S. labs are processing thousands of coronavirus tests a day, the Centers for Disease Control and Prevention (CDC) reports. But "testing availability remains a signature failure of the battle against the coronavirus in the United States," and "as the virus has spread from state to state infecting hundreds of thousands of Americans, demand for testing has overwhelmed many labs and testing sites," The New York Times reports. "Doctors and officials around the country say that lengthy delays in getting results have persisted and that continued uneven access to tests has prolonged rationing and hampered patient care." CNN looked at what went wrong in a Thursday night report.

Giroir said the 41 community testing sites around the country had proved a success, testing more than 77,000 people, mostly health care workers and first responders, NPR reports. And given the enduring testing setbacks, the HHS decision to stop sending testing materials, protective equipment, and other support to the sites had surprised some people, including members of Congress. "I'm extremely relieved that HHS has reversed its decision," Rep. Madeleine Dean (D-Pa.) told NPR News. Peter Weber

"The coronavirus continues to ravage the country, but there are signs that social distancing is beginning to work — though that does not mean we can go back to normal anytime soon, or maybe ever," Stephen Colbert said on Thursday's Late Show. Dr. Anthony Fauci suggests we continue "compulsive" hand-washing and never shake hands again. "That's bad news for secret societies," Colbert joked.

President Trump, meanwhile, is "facing the prospect of running for re-election after botching the response to a global pandemic," but his tweet about how the outbreak "must be quickly forgotten" was "a tad insensitive," Colbert said. He joked about how Passover and Easter are going to be different this year, then checked in with God, apparently self-quarantining in his Idaho cabin.

Seriously, Easter at home this year, The Late Show advised, via a burning bush.

"Easter doesn't feel at all exciting this year, probably because I've spent the last three weeks driving around looking for eggs already," Jimmy Kimmel said. "The president's been playing a game for Easter — it's called Pin the Tail on Everyone Else. He is desperate to shift blame for the fact that we were unprepared for this pandemic."

"Even with couples stuck at home with nothing to do, experts are saying we're not likely to see a quarantine baby boom," Kimmel deadpanned. "And that's a shame, because my wife and I, we say it every day: You know what would be great right now? More kids in the house. Experts say there would be a spike in birthrates if we could stop asking our significant others why they're loading the dishwasher that way."

"Love in the time of corona" is tough, Trevor Noah said at The Daily Show. "Yeah, coronavirus is the worst thing to happen to marriages since the invention of the pool boy." Divorce is skyrocketing, he said, because "quarantine is showing a lot of couples that they might love each other, but they don't like each other."

While you're trying to organize your quarantine life, the president is "hoping you'll forget that he badly botched his response to the crisis," Late Night's Seth Meyers said. "Trump thought he alone could fix it — until he saw what 'it' was" — and "nothing gives away the game of how badly Trump has handled this like Trump telling us now we have to forget about it when it's over." Watch below. Peter Weber

Yes, the Police hit "Don't Stand So Close to Me" was inspired by Vladimir Nabokov's Lolita and Sting's time as a school teacher, but on its face, it's also a perfect song for our age of social distancing. So on Thursday's Tonight Show, Sting remotely teamed up with Jimmy Fallon at the Roots to perform the song from their various homes, using whatever instruments they had on hand, real and improvised. There are two guitars and a bass but also scissors, shoes, forks, a sousaphone, a pillow, a melodica, and Fallon as a second Sting on backup vocals. The sousaphone, it turns out, makes the whole thing work. Peter Weber

President Trump tweeted Wednesday that "the Radical Left Democrats have gone absolutely crazy that I am doing daily presidential news conferences," adding that "the ratings are through the roof." But it was The Wall Street Journal's conservative editorial page that urged Trump, a few hours later, to give up his favorite "showcase" and let Vice President Mike Pence and "his first-rate health experts" run the briefings.

When the briefings started, "Trump benefited in the polls not because he was the center of attention but because he showed he had put together a team of experts working to overcome a national health crisis," the Journal editorialists said. Now each briefing devolves into a "dispiriting brawl" with the press, and "the president's outbursts against his political critics are also notably off key at this moment. This isn't impeachment, and COVID-19 isn't shifty Schiff. It's a once-a-century threat to American life and livelihood."

Trump rejected the advice.

Fox News senior analyst Brit Hume called that "a ridiculous tweet," adding that Trump "could get his views across without bragging, endlessly repeating himself, and getting into petty squabbles" with the press. Anti-Trump GOP strategist Stuart Stevens tried to imagine any recent president "bragging about his ratings" for speeches they gave after national tragedies, adding: "Decency is a place never visited by this damaged man."

Trump revels in "belittling Democratic governors, demonizing the media, trading in innuendo, and bulldozing over the guidance of experts," so "the publicity-obsessed president is unlikely to relinquish his grip on the evening sessions," The New York Times reports. But "White House allies and Republican lawmakers increasingly believe the briefings are hurting the president more than helping him," and one top political adviser said Trump was just creating ammunition for Joe Biden.

"He can't escape his instincts, his desire to put people down, like Mitt Romney, or to talk about his ratings," former Rep. Carlos Curbelo (R-Fla.) told the Times. "A leader in this sort of crisis should have a 75-to-80-percent approval rating." Still, Trump spoke only 20 minutes at Thursday's briefing, after averaging 53 minutes in recent weeks. Peter Weber