Complex sentence: \\ alpha for instance, is excluded by the syntax of types and that monotypes are included in the polytypes, thus a type has the general form\\ forall\\ alpha_1\\ dots\\ forall\\ alpha_n.
Split into simpler sentences: \\ alpha for instance, is excluded by the syntax of types. Note also that monotypes are included in the polytypes, thus a type has the general form\\ forall\\ alpha_1\\ dots\\ forall\\ alpha_n.