what images or motifs are mentioned throughout the book?

I think Briony's vivid imagination is a motif that brings both life and darkness to this novel. Her imagination defines her in many ways but is also leads into the theme of the novel itself. The broken vase is another motif of something Briony has broken and can't fix.

In the novel, McEwan incorporates many images which mirror the Tallis family. The Meissen vase symbolises Cecilia's virginity which is destroyed just as the vase is. Once the vase is repaired, the cracks are still detectable and depict Briony's uncertainty on Robbie's guilt because she starts having her doubts. The vase is completely destroyed during the war, just as the Tallis family is completely shattered. The fountain was built to mirror the Tallises' new-found wealth. However, the fountain is in a state of neglect and is falling apart just like the Tallis family. In this family, there is an element of artificiality. For instance, the portraits in the house are portraits of unknown people. Jack Tallis keeps them there to make people think that they are descended from rich people. The temple is a replica, as is the island which is where Briony encounters Lola after her rape. The conversation Briony has with Lola on this Island increases the island's symbolic value because Briony wants to step out of reality and into an imaginary world.

The heat is another motif. Characters often feel hot throughout the novel