Four things to know this week: A big Brexit week, and the world's biggest gathering

It's Monday, it's a new week, and while we won't pretend to know everything that's going to happen over the next seven days, we have some sense of what's coming up.

Here's your briefing on some of the most important and interesting stories happening in the week ahead.

1) The biggest of weeks for Brexit

What's happening？

On Tuesday, British MPs will vote on the deal struck by Prime Minister Theresa May on how to exit the European Union on 29 March.

Why does it matter？

This is one of the most important weeks building up to Brexit (if not the most important week), and the British political landscape could look very, very different by the weekend.

Mrs May is facing fierce opposition to her plan, and when MPs vote, they're likely to hand her the biggest defeat for the government in a century.

The question then becomes: what next？ What is the Plan B？ Is there a Plan B？ Could Britain leave the EU without any deal at all？

2) Trump's two yearsImage copyrightEPA

What's happening？

Sunday marks the mid-way point of Donald Trump's presidency... or a quarter of the way, if he was to win another four-year term.

Why does it matter？

Dates like this always provide an opportunity for reflection on what has been achieved during a president's term, and it will be no different in 2019.

His supporters would point to a raft of promises kept: from sweeping tax cuts, the tearing-up of trade deals and the targeting of Islamic State.

But the anniversary looks like it could take place amid the backdrop of a government shutdown that has dragged on for three weeks (unless things are resolved over the coming days).

To what extent has Trump delivered on the things he promised in his campaign？ We've answered that question here.

And if you want to understand what might happen next with the shutdown, you can read here.

3) A crowd seen from spaceImage copyrightReuters

What's happening？

In the northern Indian city of Allahabad, the Hindu festival Kumbh Mela will begin on Tuesday.

Why does it matter？

The Kumbh Mela is billed as the largest gathering of people anywhere on Earth: over 49 days, 120 million Hindu pilgrims are expected to attend.

They believe that bathing in the holy waters at the confluence of three rivers will wash off their sins and help free them from the cycle of birth and death.

The gathering is so large it will be seen from space.

The build-up to this year's event was historic too: for the first time, it featured a procession of transgender holy people last week, in a country of two million transgender people.

4) A "great national debate"

What's happening？

French President Emmanuel Macron starts a series of national debates on Tuesday that he hopes will resolve issues brought forward by the fiery "gilet jaune" (yellow vest) protests.

Why does it matter？

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Media captionFrance fuel protests: Who are the people in the yellow vests？

The protests represent the biggest challenge to Mr Macron's presidency so far.

They started in opposition to a rise in diesel prices, and even though that price hike has since been scrapped, a wider movement was born out of general anger at higher living costs.

Now, Mr Macron hopes to address concerns raised by demonstrators with a series of town-hall debates across France over the next three months.

Individual town halls will be able to host events if anyone requests, and will place "grievance notebooks" in public for people to have their say.

But planning for the debates has been somewhat chaotic, and the woman chosen to plan the events quit last week over an outcry about her salary.

Mr Macron will hope the genie is not already out of the bottle.