Kate Adie introduces stories from Ukraine, Iran, the United States and India.

February marks four years since the start of Russia’s full-scale invasion of Ukraine. Around 55,000 Ukrainian soldiers have been killed in that time and a large number are considered officially missing. Sarah Rainsford has witnessed the war since the beginning, and on her latest visit to Ukraine she met soldiers and civilians who shared stories of grief, resistance and a desire for peace.

The Iranian government recently put on a show of strength to mark the anniversary of the revolution that saw the return from exile of Ayatollah Khomeini - and the dawn of the Islamic Republic. But 47 years on, Iran has once again experienced widespread unrest, as millions of people took to the streets in nationwide anti-government protests. Lyse Doucet was recently given rare permission to report from Tehran, on condition that none of her material is used on the BBC's Persian Service.

February is traditionally Black History Month in the United States – and this year marks 100 years since the country’s first black history commemorations. Lindsay Johns recently embarked on a road trip across the Deep South, beginning at the Alma Mater of Martin Luther King in Atlanta.

BBC Budapest correspondent Nick Thorpe found himself in northern India recently when he got the news that Sir Mark Tully – long-regarded as 'the voice of the BBC' in India, had passed away. India’s Prime Minister Narendra Modi described Sir Mark as a 'towering voice of journalism'. Here, Nick pays his own tribute to Mark – and his interest in human fate, and faith.