"I Think of Three" is a sonnet written by Victorian poet Elizabeth Barrett Browning, about the pain of being absent from a lover. At the beginning of the poem, the speaker longs to be close to her partner due to his absence, but when he is in her presence again, she realizes that she does not think about him anymore.
Ultimately, this is a poem about how much better the reality of something than the thought of it. When her lover is absent, the speaker thinks about him a lot, to the point where his true self is obscured. However, when he is finally in her presence she realizes how much better it is to actually be with him than just thinking about him.
The speaker uses natural imagery to describe her thoughts, including the fact that they "twine and bud" around her partner "as wild vines about a tree." The use of natural imagery connects the passions of love to the beauty of the natural world, emphasizing the power of the speaker's feelings.