Itemize 不起作用

Question

请问为什么这不起作用？输出只有 h。

\documentclass[12pt,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[czech]{babel} 
\usepackage[left=2cm,right=2cm,top=3cm,bottom=2.5cm]{geometry}
\pagenumbering{gobble}

\begin{document}
h

\end{document}
\begin{itemize}
\item B
\end{itemize}
\end{document}

Answer 1

\documentclass[12pt,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[czech]{babel} 
\usepackage[left=2cm,right=2cm,top=3cm,bottom=2.5cm]{geometry}
\pagenumbering{gobble}

\begin{document}
hello
\begin{itemize}
\item Bravo
\end{itemize}
\end{document}