
enumerated list
I'm trying to make an enumerated list and I'm running into a few problems. I'm enclosing my list in \begin{enumerate} and \end{enumerate}, and I'm starting each point in the list with \item:
\begin{enumerate}
\item\phi, X belong to \mathcal{T}
\item\forall s \in\mathcal{T}, \bigcup_{A\in S} A \in\mathcal{T}
\item\forall s \in\mathcal{T}, s finite, \bigcap_{A\in S} A \in\mathcal{T}
\end{enumerate}
However, this is my output:
1. φ, X belongtoT∀s∈T,(union)_{A∈S}A∈T
2.∀s∈T,sfinite,(intersection)_{A∈S}A∈T
If anyone can help me out here and tell me how to get the list as it should be (definition for a topology) I would really appreciation it  I'm new to LaTeX and am still trying to figure it out. Thanks.

Try like this
\begin{enumerate}
\item $\varnothing, X\in\mathcal{T}$
\item $\forall s \in\mathcal{T}, \displaystyle{\bigcup_{A\in S}} A \in\mathcal{T}$
\item $\forall s \in\mathcal{T}, s\ \mbox{finite}, \displaystyle{\bigcap_{A\in S}} A \in\mathcal{T}$
\end{enumerate}