BEIJING, April 4 -- This Tomb Sweeping Day, Liu Shouben, a 92-year-old former Kuomintang (KMT) soldier, can finally tell people about the bloody battles he fought against the Japanese.

The holiday is a time to honor the deceased, and is also an occasion for war veterans to recount their experiences to volunteer historians, interviewers, students, and the public.

Last November, the civil affairs department in the eastern city of Nanjing officially recognized Liu as an Anti-Japanese War veteran.

"The day has come at last. The recognition is a huge comfort to my comrades who were killed in the war," Liu said.

Liu joined the KMT, or the Chinese Nationalist Party, in the spring of 1942. He fought a guerilla war alongside the Communist Party of China (CPC). However, he never mentioned his glorious past to anyone until 2012, when he was seriously ill in the hospital. His three daughters were utterly stunned.

Many KMT soldiers who made great contributions during World War II now live with difficulty due to historical and political reasons.

Following the Anti-Japanese War, which ended in 1945, the KMT forces were defeated by the People's Liberation Army (PLA), led by the CPC in the War of Liberation (1946-1949). Some KMT soldiers went to Taiwan after the war, but many others stayed on the mainland.

The KMT's contribution to the victory in the Anti-Japanese War has finally been recognized in recent years, and the soldiers' bravery has been depicted in movies and TV dramas.

Hu Lingyuan, director of the Center for Japanese Studies at Fudan University, said Chinese mainland was critical of the KMT in the first few decades after liberation, but the attitude is changing as relations across the Taiwan Strait ease.

"History will adjust itself eventually," Hu said.

This year marks the 70th anniversary of the end of World War II. War historians estimate that a total of 35 million people were killed in China during the 14-year-long war period starting from 1931.

People across China pay respect to the soldiers and civilians who lost their lives in the war on Tomb Sweeping Day, which falls on April 5 this year.

More than 1,000 students and teachers gathered at the Railway Guerrilla memorial on Thursday in Shandong Province. They laid wreaths in front of guerrillas' tombstones and stood in silent tribute.

During the Anti-Japanese War, railway guerrillas in Shandong Province led by the CPC attacked enemies on trains and blasted bridges.

When Japan surrendered in 1945, over 1,000 Japanese soldiers dropped their weapons in front of the guerrillas, who numbered no more than 100.

Just before Tomb Sweeping Day, a heritage park honoring the Flying Tigers opened in south China's Guilin City.

The Flying Tigers, officially known as the American Volunteer Group of the Chinese Air Force, were formed in 1941, led by U.S. General Claire Lee Chennault to help China drive out invading Japanese troops.

After a brief period of intensive training, Gen. Chennault led the Flying Tigers to China. In their first air battle in December 1941, the Flying Tigers downed six enemy bombers and damaged four.

By the end of the war, the Flying Tigers had shot down more than 2,600 enemy aircraft and destroyed 44 Japanese warships, which earned them great praise.

James Whitehead Jr., a 92-year-old veteran who attended the opening ceremony of the heritage park, used to fly the "Hump" back and forth during the war.

The Hump, or the "death route" over the Himalayan mountains, was flown jointly by China and the United States from 1942 to 1945 to transport military supplies from India to Southwest China.

More than 500 planes crashed along the Hump, claiming the lives of over 1,500 Chinese and American pilots. The route could clearly be seen from above as the aluminum trails of crashed plane wreckage glittered in the sunlight.

"It's very disturbing that you ask anybody on the street, and they don't know a thing about this part of history," Whitehead said.

His words echoed what Gu Xiaoming, a history professor from Fudan University, has observed in recent years. Gu said young people are strangers to this history compared with their parents and grandparents, who witnessed or participated in the war.

"We can't simply blame young Chinese for caring less," Gu said, adding the government should try harder to arouse a sense of national pride in them.

According to Shu Jian of National Defence University, of the 35 million Chinese who died in the war, over 30 million were civilians.

Japanese troops captured Nanjing, then China's capital, on Dec. 13 of 1937 and started a 40-odd-day slaughter. More than 300,000 Chinese soldiers who had laid down their arms and civilians were murdered, and over 20,000 women were raped.

In February 2014, China's top legislature designated Dec. 13 as the National Memorial Day for Nanjing Massacre Victims to mourn the Nanjing Massacre victims and all of those killed by Japanese invaders.

"The purpose of the memorial ceremony for Nanjing Massacre victims is to recall that every good-hearted person yearns for and holds a firm stance of peace, but does not try to prolong hatred," Chinese President Xi Jinping said in a speech while attending the country's first national memorial day for war victims on Dec. 13, 2014.

About 420 kilometers north of Nanjing, a memorial stone stood out at the railway guerrilla memorial. It read: "The railway guerrilla is not only the pride of the Chinese people, it is respected by all peace-loving people in the world, including the Japanese. Tamura Nobuki, a friend from Japan and a soldier of the anti-war alliance."