寂しい

In a sentence

• 最近、友達とあまり会えなくて寂しいです。

  Lately, I feel lonely because I can't meet my friends often.

  Expressing a feeling of loneliness and missing companionship.

• 彼がいなくなると寂しくなるだろう。

  I will probably feel lonely if he leaves.

  Indicating anticipated feelings of loneliness brought by someone's absence.

• 冬が終わると少し寂しい気持ちになる。

  I feel a little melancholic when winter ends.

  Describing a melancholic feeling about a seasonal change, not necessarily tied to people.