Depends on what you mean by "unify" If you just mean "describe", then it's simple. We have the Standard Model with it's exceedingly simple Lagrangian Density formed by adding Yang - Mills & Dirac fields to Klein - Gordon fields.
L=−14FμνFμν+i¯ψ∇̸ψ+¯ψϕψ+h.c.+|∇ϕ|2−V(ϕ)
Here, it is easy to identify the Yang Mills field for gluons et al, the Dirac Fields for the quwarks et al, the Klein - Gordon for the Higgs, a scalar field.
If you mean "unify" in the sense of grand unification and such, then it's a bit more complicated.
Grand Unification
Refers to the unification (meaning: having a simple group as the gauge group, as opposed to the Standard Model whose gauge group is SU(3)×SU(2)×U(1); yet describe the Standard Model, since it's experimentally verified to a pretty high degree).
Examples include
Theories of Everything
Better than GUTs; unify (quantised) gravity too. Examples include string-theory.