Break, break, break
Apostrophe device
Tennyson addresses the sea directly—a device called apostrophe. The sea can't respond, mirroring his inability to speak his grief in line 3.
Conditional 'would'
Not 'I wish' but 'I would that'—archaic conditional phrasing that emphasizes impossibility. He knows words won't come.
Anaphora pattern
Three consecutive 'O' exclamations building emotional intensity. The third breaks the pattern with 'But O'—the turn from observation to personal loss.
Final negation
The only absolute statement in the poem. Everything else is observation or longing—this is certainty about loss.