Theorem 7.1 (Green, Manners, Tao, Gowers). There is a polynomial p with the following property:

If n and A𝔽2n is such that |A+A|C|A|, then there is a subspace H𝔽2n of size at most |A| such that A is contained in the union of at most p(C) translates of H. (Equivalently, there exists K𝔽2n, |K|p(C) such that AK+H).