M-theory on G2 manifolds is an analog of string theory on symplectic manifolds. The role of holomorphic curves with Lagrangian boundary conditions is replaced by associative submanifolds with coassociative boundary conditions. The work of Fukaya-Oh related holomorphic disks in cotangent bundles with Morse flow lines in Lagrangian submanifolds. Wang, Zhu and I generalized this to the G2 setting, namely thin associative submanifolds can be constructed from regular holomorphic curves in coassiciative submanifolds. This can be used to construct new examples of associative submanifolds.