The slogan about the unforgettable teacher's kindness is as follows:

1. The teacher's kindness is like a mountain and will never be forgotten.

2. Be grateful to teachers and contribute to society.

3. Respect teachers and teach, and pass on the legacy from generation to generation.

4. The teacher’s kindness is as deep as the sea and will be engraved in my heart.

5. Thank you teachers, they are the beacons that illuminate our way forward.

6. My deep gratitude to you will always be unforgettable. Thank you for your hard work.

7. Teaching is like spring breeze, and teacher’s kindness is as deep as the sea.

8. The spring breeze turns into rain and nourishes all things. My teacher’s kindness is unforgettable and will remain in my heart forever.

9. Be grateful to teachers, they are the gardeners of the soul, sowing hope and harvesting the future.

10. A teacher’s kindness will be unforgettable and will be remembered for a lifetime. Thank you teacher, always respect me.

11. Love, kindness, and gratitude

12. Gratitude starts from the heart, and love warms each other.

13. Once a teacher, a lifelong father. A teacher’s kindness will be unforgettable and his love will last forever.

14. Learn to be grateful, be grateful for everything, make gratitude a habit, and make life better!

15. People must have a grateful heart, and then have a calm mind. A calm mind means being open-minded, and being open-minded means knowing how to advance and retreat.

16. Turn a grateful heart into a grateful offering.

17. Gratitude is not only a moral character, but also a responsibility.

18. I am moved one after another; I receive grace one moment at a time; I am grateful all my life.

19. Repay kindness with a ring of grass, throw it with a peach, and repay it with a plum.

20. Sheep have the kindness of kneeling down to breastfeed, and crows have the kindness of feeding back.

21. Gratitude is tolerance; gratitude is warmth; gratitude is happiness!

22. Be grateful every day and be happy forever!

23. Love, kindness, and gratitude.

24. Words come from the mouth, kindness comes from the heart.

25. Be grateful in your heart and repay in your deeds.

26. Learn to be grateful and learn to be a good person.

27. Be thankful, start with me, start with small things.

28. Drink from its spring, think about its source, eat its fruit, and remember its tree.

29. The way of enlightenment, the love of a teacher, the teacher’s kindness will be unforgettable, and the teacher’s love will last forever.

30. Always be moved and always be grateful.

31. Gratitude starts from the heart and let love warm each other.

32. Whoever says nothing will be rewarded with three rays of spring.

33. A drop of kindness should be repaid by a spring.

34. Learn to be grateful, and gratitude will make you a strong person; learn to be grateful, and gratitude will make your world full of sunshine.

35. Understand that "gratitude" is an attitude towards life, a virtue, and the minimum moral code for being a human being.