答案1
像这样
\begin{tikzpicture}[xscale=8]
\draw[-][draw=red, very thick] (0,0) -- (.5,0);
\draw[-][draw=green, very thick] (.5,0) -- (1,0);
\draw [thick] (0,-.1) node[below]{0} -- (0,0.1);
\draw [thick] (0.5,-.1) node[below]{$1/2$} -- (0.5,0.1);
\draw [thick] (0.5,-.1) node[above]{$L,R$} -- (0.5,0.1);
\draw [thick] (1,-.1) node[below]{1} -- (1,0.1);
\end{tikzpicture}