Here are the suggested word forms for the blanks in the sentences provided:

26. The result of the experiment was **satisfactory** (satisfy).
27. His **priority** is always for his son. (prior)
28. It was **considered** (consider) you to play the piano while I was asleep. It’s bothering me.
29. She looked **proudly** (proud) at the result of her work.
30. I’ve lost all **feeling** (feel) in my legs.
31. He is **celebrated** (celebrate) for his intelligence.
32. Her was a shock to him. **(die)** → Not applicable, but could say: "Her death was a shock to him."
33. Speech is a **distinguishable** (distinguish) feature of human beings from the animals.
34. The patient is getting on **satisfactorily** (satisfy).
35. Your proposal is being **considered** (act).
36. I felt such a sense of **freedom** (free) up in the hills alone.
37. Beethoven and Chopin were leading Romantic **composers** (compose).
38. Mary is reading a **humorous** (humor) story.
39. Only in his dreams does he give **expression** (express) to his fears.
40. He treated us with **generosity** (generous) and thoughtfulness.
41. The renovation process and **decorations** (decorate) took four months.
42. Easter is a **joyful** (joy) festival which is celebrated in many countries.
43. He won the **nomination** (nominate) as my class leader.
44. There are a lot of **national** (nation) festivals in my country throughout the year.
45. New Year’s Day is a **national** (nation) festival.
46. Mary is one of his **acquaintances** (acquaint).
47. Our neighbors are very **considerate** (consider); they’re always playing loud music late at night.
48. The supermarket is always **crowded** (crowd).
49. Tuan is an active student. He takes part in a lot of **activities** (act).

Feel free to ask for further clarification or assistance!