We study cosmological perturbations for k-essence and kinetic gravity
    braiding models in the context of the two-field measure theory (TMT).
    Considering scalar perturbations and the uniform field gauge, we obtain the
    sound speed of the fields and present a stability analysis by means of the
    kinetic matrix and the mass eigenvalues. For k-essence models, in the two-field
    measure theory, the speed of propagation of the field is modified completely
    due to the new measure field and it gives rise to crucial differences with
    respect to the case without new measure. The stability analysis gives a
    physical viable model for the Universe. For the kinetic gravity braiding models
    in the two-field measure theory we get that, in general, the speed of
    perturbations is equal to the speed of light which is a consequence of the
    properties of the new measure field. In the later case, there is always a ghost
    field. Furthermore, we calculate general expressions for the mass eigenvalues
    and find, for an explicit example, the existence of tachyonic instabilities.

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