(CNN) Former US Ambassador to Ukraine Marie Yovanovitch testified publicly on Friday in the impeachment inquiry, telling her story about how President Donald Trump recalled her from Ukraine and how she felt "intimidated" by his real-time attacks against her on Twitter.
The career diplomat was sworn in shortly after 9 a.m. ET and answered questions for several hours before the House Intelligence Committee.
Things will heat up next week on Capitol Hill, with three days of impeachment hearings scheduled, and Yovanovitch's appearance gave some clues for how future hearings might play out.
Here's five big things we learned from Friday's hearing.
Friday's hearing only amplified the questions for Gordon Sondland, the American ambassador to the European Union, who is scheduled to appear Wednesday.
In her testimony, Yovanovitch described the unusual role Sondland held in the Ukraine policy: he claimed to have oversight, even though Ukraine isn't in the European Union.
"I would say that all EU ambassadors deal with other countries, including aspiring countries, but it is unusual to name the US ambassador to the EU to be responsible for all aspects of Ukraine," she said at a contentious moment as a Republican member of Congress sought to cut her off.
She also detailed Sondland's advice to "go big" in her public praise of Trump in an attempt to keep her job.
Like Wednesday's first public hearing, the testimony raises more questions for Sondland. Even as Friday's hearing was unfolding, an aide from the US embassy in Kiev was appearing in closed deposition to detail a phone call he overheard between Sondland and Trump that places the President closer to the alleged pressure campaign.
Democrats are eager to hear Sondland clarify his own answers about his interactions with Trump, and his perceptions of what Trump wanted him to execute in Ukraine. Republicans, meanwhile, are looking to examine how close Sondland actually is to the President, and to test his various accounts for inconsistencies.
Maybe for that reason, Sondland is set to appear solo at next week's hearing.
The proceedings on Friday were different than the first open hearing on Wednesday, which featured two plain-spoken diplomats who offered important but occasionally dull testimony.
On the other hand, Yovanovitch had a personal story to tell. Her career suffered at the hands of Trump and his personal attorney Rudy Giuliani, who lobbied for her removal. She was pulled from Ukraine in April after being told that the President no longer wanted her as ambassador.
"After 33 years of service to our country, it was terrible," Yovanovitch said, recalling the day she learned that she needed to come home. "It's not the way I wanted my career to end."
Next week's witnesses won't have the same gripping story to tell of a "concerted campaign" against them and potential political retaliation by the President. .
This was the week Republicans felt — at long last — they had a strategy for combating Democrats' impeachment inquiry. After weeks of twisting in the wind without a clear directive from the White House, a pair of new hires and better coordination were welcomed by many Trump allies.
Then came the tweet. Less than an hour into Yovanovitch's testimony, Trump wrote: "Everywhere Marie Yovanovitch went turned bad," citing her posts in Somalia and Ukraine. It landed like a thud. House Intelligence Chairman Adam Schiff read the tweet during the hearing, and said during a recess that it could amount to "witness intimidation in real time."
Even many Republicans distanced themselves.
"I disagree with the tweet," Rep. Elise Stefanik said during a break. When questioning resumed, many Republicans went out of their way to praise Yovanovitch's service, with one calling her "tough as nails" and "smart as hell."
It was a sign Trump and his allies in Congress remain in different places as the impeachment proceeding advances. Despite bringing new advisers aboard tasked with aligning a GOP strategy, Trump showed he still has the power to upend those efforts with a single tweet.
Trump defended himself in the afternoon — "I have the right to speak," he said at the White House — but he found few voices willing to second the substance of his tweet in Congress.
A clear split emerged throughout the day over who was actually tackling corruption in Ukraine.
Democrats held up Yovanovitch as the true corruption-fighter, someone who "named names" in Kiev. She was so dogged in her fight, Democrats said, that she rattled two of Giuliani's associates who were trying to do shady business in Ukraine, so they plotted to to taker her down with "corrupt" Ukrainian leaders, like former prosecutor general Yuriy Lutsenko.
"The President praises the corrupt -- Lutsenko -- and condemns the just -- you," Schiff, the Democratic chairman of the committee, told Yovanovitch in his closing remarks.
Meanwhile, Republicans portrayed Trump as the one who was trying to clean up Ukraine by asking the new Ukrainian president to launch investigations into former Vice President Joe Biden and his son, who served on the board of a Ukrainian energy company named Burisma.
Under questioning from GOP lawmakers, Yovanovitch acknowledged that there was "endemic corruption" in Ukraine and that Burisma's oligarch owner had a history with corruption. And she expressed concerns about the ethics of Biden's son working on the board while his father led the Obama administration's policy on Ukraine. But she didn't cede an inch on her own record. There is no evidence of wrongdoing by either Biden in Ukraine.
"Mr. Giuliani should have known those claims were suspect, coming, as they reportedly did, from individuals with questionable motives and with reason to believe that their political and financial ambitions would be stymied by our anti-corruption policy in Ukraine," Yovanovitch said.
During the two public hearings, Republicans have sought to bolster the credibility of the future witness they believe can rebut claims Trump committed bribery in his dealings with Ukraine.
Kurt Volker, the former US special envoy to Ukraine, is set to appear next Tuesday. He was one of the eight witnesses Republicans submitted for public testimony. (Of them, only Volker and two other administration officials, Tim Morrison and David Hale, were accepted by Democrats.)
During Volker's closed-door deposition last month, he described the efforts undertaken by Giuliani in Ukraine. But he insisted there was no "quid pro quo" in Trump's requests that Ukraine investigate the Bidens or look into conspiracy theories about the 2016 election.
Republicans are hoping to boost Volker's standing before he appears. The GOP staff attorney, Stephen Castor, asked Yovanovitch if Volker was "a man of honor" and a "brilliant diplomat," descriptions she agreed with.
It echoed a line of questioning on Wednesday, when Castor asked two career diplomats similar questions. Bill Taylor, the top US diplomat in Ukraine, said Volker's "first priority is clearly the United States."
When Volker appears on Tuesday, Republicans hope viewers remember the credibility imbued by the previous witnesses — at least if Volker maintains his view that Trump's actions didn't amount to a quid pro quo.