省略号在证明质量成本时意味着什么?

这是本在线课程中出现的证明 https://softwarefoundations.cis.upenn.edu/plf-current/StlcProp.html#lab222 .

Proof with eauto.
  remember (@empty ty) as Gamma.
  intros t t' T HT. generalize dependent t'.
  induction HT;
       intros t' HE; subst Gamma; subst;
       try solve [inversion HE; subst; auto].
  - (* T_App *)
    inversion HE; subst...
    (* Most of the cases are immediate by induction,
       and [eauto] takes care of them *)
    + (* ST_AppAbs *)
      apply substitution_preserves_typing with T11...
      inversion HT1...
Qed.

椭圆在这条线上做什么? apply substitution_preserves_typing with T11...