20 commonly used words suitable for C1 level students, along with their meanings and examples:

1. Coincidence
Meaning: A situation in which events happen at the same time by chance.
Example: "Meeting my childhood friend at the airport was a happy coincidence."

2. Harmonious
Meaning: Having a pleasant arrangement of parts; free from disagreement or dissent.
Example: "The team worked together in a harmonious manner to achieve their goals."

3. Scent
Meaning: A distinctive smell, especially one that is pleasant.
Example: "The scent of flowers filled the air in the garden."

4. Crush
Meaning: A brief but intense infatuation for someone, typically someone unattainable.
Example: "She had a crush on the movie star since she was a teenager."

5. Fleeting
Meaning: Lasting for a short time; transient.
Example: "The feeling of joy was fleeting, disappearing as quickly as it had come."

6. Throw out
Meaning: To dispose of something; to get rid of something.
Example: "We decided to throw out the old furniture and buy new ones."

7. Wordy
Meaning: Using or expressed in too many words; verbose.
Example: "His explanations were always wordy, making it hard to follow his train of thought."

8. Calm
Meaning: Peaceful and quiet; without worry, anger, or excitement.
Example: "The lake was calm and still in the early morning light."

9. Unrealistic
Meaning: Not in agreement with what is possible or likely; not realistic.
Example: "Her dream of becoming an astronaut seemed unrealistic given her fear of heights."

10. Whisper
Meaning: To speak very softly or quietly.
Example: "She whispered the secret to her best friend."

11. Eternal
Meaning: Lasting forever; without end or beginning.
Example: "Their love for each other was eternal, enduring through all challenges."

12. Deep
Meaning: Having great intensity or profundity.
Example: "The conversation they had was deep and meaningful."

13. Vanishing
Meaning: Disappearing suddenly and completely.
Example: "The vanishing sun dipped below the horizon, leaving the sky dark."

14. Glowing
Meaning: Giving out steady light or heat without flame; brightly shining.
Example: "The glowing embers of the fire warmed their faces."

15. Light
Meaning: Gentle and delicate.
Example: "The light breeze rustled the leaves of the trees."

16. Magnificent
Meaning: Very beautiful or impressive; grand or splendid.
Example: "The view from the top of the mountain was magnificent."

17. Trace
Meaning: A very small amount of something.
Example: "There was no trace of the missing keys anywhere in the house."

18. Quiet
Meaning: Free from disturbance or interruption.
Example: "The library was quiet, except for the sound of pages turning."

19. Sweet
Meaning: Pleasing to the senses; having a pleasant taste or smell.
Example: "The sweet aroma of freshly baked cookies filled the kitchen."

20. Peace
Meaning: A state of tranquility or quiet; freedom from disturbance.
Example: "The peace and quiet of the countryside were a welcome relief from the noise of the city."