1. It is extremely dangerous for a ship to get lost at sea. But if they find the North Star and follow its direction, they can be saved. As long as there is love in your heart, you are fearless of any difficulties and obstacles. Love is the "North Star" in lovers' hearts. With its guidance, the ship of love will not lose its way.
2. The surging and unpredictable sea symbolizes the difficulties and obstacles on the road of true love: "It is a permanent mark/it looks at the storm and never wavers."
It makes weak-willed lovers lose the direction of love, but the eternal mark on the sea is a symbol of true love. As long as there is true love in your heart, any difficulty can be overcome.
Extended data:
1609, Shakespeare published Sonnets, which is his last non-dramatic work. Scholars can't confirm the completion time of each of 154 sonnets, but there is evidence that Shakespeare wrote these sonnets for a private reader throughout his creative career.
A few analysts believe that the published works are based on Shakespeare's intentional arrangement. It seems that he has planned two opposite series: one is about a dark-skinned married woman's uncontrollable desire.
Baidu Encyclopedia-Shakespeare's Sonnets