Under the Thames Bank in front of Tate Modern, the artist has created a way to return natural products to nature. She writes "What we need to be" in sea salt on the river bank, an unpunctuated sentence that feels like a question to the sea and a statement to herself. When the sea water flowing into the Thames rises and falls again and again, the waves beat and erode this sentence. With the melting of sea salt, this question that human beings put forward to themselves and nature gradually disappears into the sea water. It is like throwing stones into the empty valley, and all the inpuzzles and questions are hidden into the endless sound of the waves.