WASHINGTON - President Donald Trump is expected to be impeached by the House next week over claims he abused his power and obstructed Congress when it tried to investigate.

How did we get here?

The story is complicated, but the questions at the heart of the impeachment matter are simple.

Did the president dial back support for a U.S. ally as a way of extracting a political favor from the country's leader? And was the request for a political favor inappropriate in the first place?

These are the issues confronting lawmakers as they decide whether to vote yes or no on two articles of impeachment next week.

Here are five simple questions that explain what happened, where the parties disagree and what comes next.

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1. What did Trump do?

For the past three months, Washington has been consumed by the following drama.

A U.S. president pressures the leader of a small country to announce a corruption investigation. The target would be a former vice president who is running to beat the president in the next election.

The request for a political favor is unusual and hangs over the foreign leader. His country is at war with another world power, and he does not want to alienate the United States, which has taken his side.

The leader's position soon becomes more difficult. It emerges that the White House has stopped the flow of U.S. funds to his country's military. The president is also holding back a gesture that would cement the alliance in the eyes of the world - a meeting between the two in the Oval Office.

This is what took place between Trump, the president, and Ukraine, the smaller country. But what it means is up for debate.

In a phone call on July 25, Trump asked Ukrainian President Volodymyr Zelensky to "do us a favor." He suggested that former Vice President Joe Biden had engaged in corruption on behalf of his son Hunter, who had served on the board of a Ukrainian energy company.

"If you can look into it ... It sounds horrible to me," Trump said.

The phone call alarmed several U.S. officials, prompting an investigation in Congress that turned into the impeachment inquiry. Testimony from witnesses revealed the broader story, including the withholding of military aid and an Oval Office meeting for Zelensky.

The investigation was led by Democrats, who hold a majority of seats in the House. Trump, who says he did nothing wrong, refused to cooperate, and ordered the executive branch to ignore subpoenas for documents and testimony from witnesses.

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2. What do Democrats say?

Democrats argue that Trump violated two broad standards that provide grounds for impeachment. As a result, the House will vote on two articles of impeachment.

The first accuses Trump of abuse of power.

Democrats say that by asking Zelensky to announce an investigation into the Bidens, Trump "solicited the interference of a foreign government" in the 2020 presidential election. They say Trump pursued this goal by withholding military aid and an Oval Office meeting. In other words, he conditioned "acts of significance" by the U.S. government on Ukraine's cooperation with his wishes, they say. (The nearly $400 million in congressionally appropriated aid was eventually released, after Democrats announced an investigation.)

Trump's actions "compromised the national security of the United States" and "undermined the integrity of the United States democratic process," the first article of impeachment states.

The second article accuses Trump of obstruction of Congress.

Democrats say that the president's effort to thwart the impeachment inquiry violated the Constitution and undermined the balance of power that defines the U.S. government.

Specifically, they say that by ordering the executive branch not to cooperate with the investigation, Trump took away powers that properly belong to the House. This strategy allowed him to "seize and control" the impeachment function, they say.

"In the history of the Republic, no President has ever ordered the complete defiance of an impeachment inquiry," the articles state. "... This abuse of office served to cover up the President's own repeated misconduct."

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3. What do Republicans say?

Nearly all Republican members of Congress are standing by Trump, arguing that Democrats have misinterpreted his actions in a sinister light because they dislike him.

These Republicans argue that Trump was acting on valid concerns about corruption when he asked Zelensky to investigate the Bidens. They say that Joe Biden's status as a possible 2020 opponent was not a factor, and that Trump was not trying to undercut him politically.

The idea that Trump's only motivation in dealing with Ukraine was fighting corruption informs almost all Republican arguments against impeachment. If this was the case, then Trump was within his rights to pressure Zelensky and to withhold military aid until he saw action, they say.

Most of all, Republicans have decried the impeachment inquiry itself, calling it unfair to Trump and to their party - including the investigation, the public hearings and the committee votes. They argue that Trump was justified in refusing to cooperate with a "sham" process. They also say that the evidence gathered by Democrats is incomplete and indirect - not enough to prove that Trump committed wrongdoing.

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4. What happens next week?

The articles of impeachment passed the House Judiciary Committee on Friday. They will move to the Rules Committee on Tuesday and to the House floor on Wednesday. A final vote is expected to take place that day, mostly along party lines, leading to Trump's impeachment.

It's a common misconception that impeachment by the House forces a president from office. In fact, the task of deciding whether to remove a president falls to the Senate.

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5. What happens next year?

If the House approves the articles of impeachment, the Senate will be required to have a trial, where the president will either be convicted or acquitted based on the charges laid out in the articles. Senate Majority Leader Mitch McConnell, R-Ky., has said that a trial will be short and will begin in early January.

Because Republicans hold a majority of Senate seats, Trump is expected to be acquitted, which means he would remain in office.