Abstract: | Let a function f ∈ C[−1, 1], changes its monotonisity at the finite collection Y:= {y1, ..., ys} of s points yi ∈ (−1, 1). For each n ≥ N(Y), we construct an algebraic polynomial Pn, of degree ≤ n, which is comonotone with f, that is changes its monotonisity at the same points yi as f, and where N(Y) is a constant depending only on Y, c(s) is a constant depending only on s and ω2 (f,t) is the second modulus of smoothness of f. |