Explanation:

Champaran Satyagraha 1917 : European planters forced the farmers to cultivate Indigo on atleast 3/20 (Tinkathiya) parts of their land. Rajendra Prasad, Mazhur-ul-Haq, J.B. Kriplani, Mahadev Desai accompanied him. An enquiry was set up to alleviate miseries of which even Gandhi was a member.
Kheda Satyagraha 1918: Kheda peasants refused to pay revenue due to failure of crops. After Satyagraha the government issued instructions to collect revenue only from those who could afford to pay. Indulal Yagnik & Vallabh Bhai Patel supported Gandhi.
Jallianwala Bagh Massacre 1919: Demanded to know the whereabouts of Satyapal and Kitchlew throught the reciting of the poem ‘Fariyad’ on the day of Baisakhi (13th April, 1919). Martial law was proclaimed later at Lahore, Gujarat & Layal with curfew at Amritsar. An enquiry was setup under Hunter which was described by Gandhiji as “White Wash”. Rabindranath Tagore renounced his title.
Non Cooperation 1920-22: Approval at Congress session in 1920. Leaders like Mohammad Ali Jinnah, Annie Besant & Bipin Chandra Pal not in agreement & left the congress. Students took their names off school. Kashi Vidyapeeth, Bihar Vidyapeeth, Jamia Milia Islamia were set up.