US President Barack Obama is making one of the most critical speeches of his presidency¹, as he faces Congress over his plans for healthcare reform.

美国总统奥巴马将要做他在位期间一次至关重要的演讲，他将就医疗改革面临国会的审核。

Mr Obama has said he will use the prime-time speech to clarify what changes he is proposing.

According to the White House, Mr Obama will say after 100 years of effort to reform healthcare, he wants to be the last president to deal with the issue.

He will say that if reforms are not produced, more Americans will die.

Members of Congress are preparing to fight over details of the reforms, as they return after the summer recess（休息，放假）.

In an interview with ABC News broadcast earlier in the day, Mr Obama said the point of his speech would be to ensure that people understood exactly what was being proposed.

He said he also wanted to remain open to new ideas.

He told ABC he wanted to "make sure that Democrats² and Republicans understand that I'm open to new ideas, that we're not being rigid³（僵硬的，刻板的） and ideological⁴（意识形态的） about this thing but we do intend to get something done this year".

Mr Obama said that when he initially⁵ raised the proposals he had "probably left too much ambiguity（含糊，暧昧）".

Now, he said, he now wanted to "dispel⁶（驱散） some of the myths and, frankly⁷, silliness that's been floating out there for quite some time".

'False notions'

Analysts⁸ say the speech is perhaps the most critical juncture⁹（接合，连接） of Mr Obama's presidency so far.

Healthcare reform has been the central issue of his change agenda but has divided both the US public and the country's political establishment.

One problem is that the issue is so complex many Americans say they do not fully¹⁰ understand the proposals.

Mr Obama said he wanted to address the "ridiculous idea" that the bill includes proposals for so-called death panels - doctors determining who should receive treatment.

He would also tackle "false notions" that the moved was aimed at providing health insurance to illegal immigrants and the broader notion（观念，想法） that the government was taking over health care.

The BBC's Kevin Connolly, in Washington, says the president will need all his oratory¹¹（讲演术） skill to rescue his hopes for reform.

He is facing almost unanimous（全体一致的） opposition¹² from Republicans, who are uneasy about the idea of government-run healthcare and who have accused Mr Obama of attempting to introduce a "socialist¹³" policy.

There are, in theory, enough Democrats in Congress to approve the changes.

But in practice, the party is deeply divided between those that want a publicly-run insurance scheme and those alarmed by the borrowing necessary to fund it, our correspondent says.