使劲 (shǐ jìn): to exert effort

He pushed the old wooden door with all his strength, but the door still didn't budge.

My little sister stood on her tiptoes with great effort, trying to reach the storybook on the top shelf.

Hearing the good news, he slammed the table with force, stood up and cheered loudly.

During the tug-of-war, all the students pulled backward with all their might, their faces turning red.