1. Bamboo: Bamboo will not wither in the cold winter, but it will remain green forever, which reminds people of those who stick to their posts and keep their indomitable spirit no matter how difficult the environment is. For example, doctors, teachers and volunteers in remote areas.

2. Plum blossoms: Plum blossoms bloom in the cold winter, symbolizing tenacity and perseverance. This reminds people of those who are indomitable in the face of difficulties and challenges, such as researchers and artists.

3. Bees: Bees are industrious insects. They tirelessly collect nectar from flowers and strive for the continuation of life. This reminds people of those unknown workers, such as farmers, cleaners and nurses. They work hard and contribute to the prosperity and stability of society.

4. Street lamps: Street lamps illuminate the road in the dark night and make people walk safely. This reminds people of those unknown guardians, such as police, security guards, firefighters and so on. They still stick to their posts in the dead of night to ensure social order and people's safety.

These things represent people who have contributed in different ways. Although they are not famous, their contribution is indispensable to society.