答案1
\documentclass[tikz, border=1cm]{standalone}
\begin{document}
\begin{tikzpicture}
\fill (-1,0) circle[radius=0.1];
\fill (1,0) circle[radius=0.1];
\draw[very thick] (-1,0) to[out=55, in=125, looseness=1.5] (0,0) to[out=-55, in=-125, looseness=1.5] (1,0);
\draw[very thick] (-1,0) to[out=-55, in=-125, looseness=1.5] (0,0) to[out=55, in=125, looseness=1.5] (1,0);
\end{tikzpicture}
\end{document}