1. He feels gloomy.

2. He feels blue.
3. He feels depressed.
4. He feels down.
5. He feels melancholy.
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Thank you for your help.
They all seems to be correct?
What about #5? Can we use that way?
Which ones are commonly used?

All are correct and commonly used.

Yes, all of the phrases you mentioned are correct and can be used to express a similar feeling. However, some phrases may be more commonly used than others, depending on the context and personal preference.

1. "He feels gloomy" suggests a feeling of sadness or darkness.
2. "He feels blue" is an idiomatic expression meaning to feel sad or down.
3. "He feels depressed" indicates a more intense and prolonged feeling of sadness or low mood.
4. "He feels down" is a more casual way to express feeling sad or disheartened.
5. "He feels melancholy" implies a deep and reflective sadness or pensive mood.

In terms of common usage, "feeling blue" and "feeling down" are probably the most frequently used expressions. "Feeling depressed" is also commonly used but tends to carry a stronger connotation and is often associated with a clinical diagnosis. "Gloomy" and "melancholy" are slightly less common but are still used to convey a specific type of sadness. Ultimately, the choice of phrase depends on the individual's personal preference and the level of emotion they want to express.