15. Sore (adj): /sɔː(r)/ Adolorido
Painful and uncomfortable, usually as a result of an injury, infection, or too much exercise.
Example: I always feel stiff and sore after doing exercises.

16. Spoil (v): /spɔɪl/ Estropear
To affect something in a way that makes it worse, less attractive, or less enjoyable.
Example: I don't want to spoil this moment.

17. Stiff (adj): /stɪf/ Rígido
Firm and difficult to bend
Example: My neck is getting stiff.

18. Thorough (adj): /ˈθʌrə/ Minucioso
Including everything that is possible or necessary.
Example: He has a thorough understanding of the marketing.

19. Unaware (adj): /ˌʌnəˈweə(r)/ Inconsciente
Not realizing that something exists or is happening.
Example: Jose seemed unaware that there was a dog in the room.

20. Utter (v): /ˈʌtə(r)/ Murmurar
To say something.
Example: She uttered a sound.

a. Practice:
Choose one word from the list above and fill in the blanks.

1. We need to  this new product. as soon as possible.

2. My nephew loves learning new things. He's always  to learn.

3. Let's wait until she  from this disease. She will feel better.