In William Wordsworth's poem "I wondered lonely as a cloud" the daffodils represent his happiness and inspiration. The daffodils make him forget about his loneliness.
The daffodils help him to forget that he doesn't have anyone and is depressed. First, he is walking alone as he notices these daffodils under trees unnoticeable as he is towards people: "I wandered lonely as a cloud/that floats on high o'er vales and hills/when all at once I saw a crowd/a host of golden daffodils/decide the lake beneath the trees/fluttering and dancing in the breeze". Next, he states that they were never-ending and dancing in the breeze: "They stretched in never-ending line/along the margin of a bay/ten thousand saw I at a glance/tossing their heads in sprightly dance". Then, he notices the waves, too, but the daffodils out do the waves and this makes him joyful: "The waves beside them danced; but they/out-did the sparkling waves in glee/a poet could not but be gay". Finally, as he lays on his couch alone he remembers the daffodils and his heart fills with joy and inspire him to dance with them: "For oft, when on my couch I lie/in vacant or in pensive mood/they flash upon that inward eye which is the bliss of solitude/and then my heart with pleasure fills/and dances with the daffodils". So, a person can see how the daffodils make him happy.
In conclusion, the daffodils make his heart fill with pleasure and they also inspire him to dance, too. So, these daffodils make him feel like he isn't alone and he becomes happy because of this.