Has the British offer of citizenship to Hongkongers violated the 1984 Sino-British Joint Declaration?
The UK doesn't have a set back-up plan when a prime minister is unwell, but there are clear procedures in place.
To understand what is going on, it helps to look back at past leaders and their first secretaries.
The United Kingdom does not have a written constitution or a specific plan for what to do if the prime minister is too ill to perform official duties.
Johnson is the least popular among women MPs and Jeremy Hunt managed to get a vote from the European Research Group.
Brexit will inevitably dominate this campaign, but the next prime minister also needs positions on austerity, party unity and how to actually survive in parliament.
The party does have younger members, but their voices are not being heard as the leadership contest gets underway.
Boris Johnson, Amber Rudd, Dominic Raab? Who will be the next prime minister?
The PM is in a tight spot, but can anyone else lead the nation into Brexit?
Controlling immigration was the most important concern for Brexit voters and May's deal does that.
It sparked a series of government resignations, but what's actually in Theresa May's Brexit plan?
Despite the problems that lie ahead with the Brexit plan Theresa May hammered out at Chequers, the EU prefers a Brexit deal rather than a 'no deal'.
After the resignation of David Davis, Dominic Raab has a tough job ahead of him at the Department for Exiting the European Union. Here are some lessons he could learn from his predcessor.