努力 (doryoku) means effort or exertion. It refers to the hard work or serious attempt made to achieve something. It implies perseverance and dedication, often in the face of difficulty. It's essential for success. For example, '成功のためには努力が必要だ。' (Effort is necessary for success.)

努力 (どりょく) は目標達成のために一生懸命頑張ること。成功には努力が不可欠です。例：努力が報われる。