Read the following text and fill in each gap with a suitable word based on the information of the text: 

May Day or International Worker's Day is observed on May 1 all over the world today to commemorate the historical struggle and sacrifices of the working people to establish an eight hour workday. It is a public holiday in almost all the countries of the world. 

Since the Industrial Revolution in the 18th and 19th centuries in Europe and the US, the workers in mills and factories had been working a long shift, fourteen or even more hours a day. 

On May 1st in 1886, inspired by the trade unions, half of the workers at the McCormick Harvesting Machine Company in Chicago went on strike demanding an eight hour workday. Two days later, about 6000 workers brought out a rally addressed by the labour leaders. Suddenly about 200 policemen attacked them with clubs and revolvers. One striker was killed instantly, five or six others were seriously wounded and many others were injured. 

The events of May 1, 1886 are a reminder that workers will continue to be exploited until they stand up and speak out to gain better working conditions, better pay and better lives. 

People all over the world observe May 1, as International Workers' Day to (a) ________ the historical struggle and sacrifice made by the working class people. For their great (b) _______ , now the workers can enjoy an eight hour workday. It was a historical struggle (c) _____ the employers and employees. This day reminds that the (d) _______ will be exploited until they raise their (e) ______ for their rights and privileges.