How to use align gather in itemize or list environment?

I would like to number each equations under the itemize environment by using align or command.However it doesn't work well.Thank you for your patience in advance. The errors: Runaway argument? with\quad U(c_t,l_t)&=\theta \ln c_t+(1-\theta )\ln (1-l_t), 0<\theta \ETC. ! Paragraph ended before \align was complete. \par But I don't know how to correct it. My codes are following:

\section{Economic Environment}
\begin{itemize}
\item{Consumption of a representative agent at period-t:}$c_t$.
\item{Labor of a representative agent at period-t:}$l_t$.

\item{The expected value of lifetime utility:}

\qquad$\biggl[\sum_{t=0}^{\infty}\beta^t U(c_t,l_t)\biggr]$
\begin{align}
\item {Final output:}y
\item {Capital of equipment and Structure:}k&=k_e+k_s.\\
\item {Utilization rate of equipment:}h.
\item {Total factor productivity(TFP):}z.
\item{Production technology:}
0<\alpha_e,\alpha_s,\alpha_e+\alpha_s<1 \\
\item{Investment in equipment and structures:}

\item{Adjustment costs that can be used for consumption, c,investment in
structures and equipment:}

\phi_e,\kappa_e>0,\\
\intertext{and}a_s&=A_s(k_s',k_s)\\
&=\phi_s{(k_s'-\kappa_s k_s)}^2/k_s.
\item{Resource constraints:}

\item{The stock of structures accumulation equation:}

\item $q$: The current state of the technology for producing equipment.
\item{The equipment accumulation equation:}

\item{Equipment depreciation function:}

\item{Process of TFP:}

\qquad where $\zeta_{t+1}$ follows the distribution
function Z(\zeta'|\zeta)&=Pr\{\zeta_{t+1}=\zeta'|\zeta_t=\zeta\}.\\
\item{Process of investment specific technology:}

\qquad where $\eta_{t+1}$ follows the distribution
function $H(\eta'|\eta)=Pr\{\eta_{t+1}=\eta'|\eta_t=\eta\}.$
\end{align}
\end{itemize}


Thank you so much!

• Full minimal example please. Remember gather require the amsmath package, but since you did not post a full minimal example we do not know if you loaded it – daleif Apr 1 '18 at 16:16
• I used amsmath package. i.stack.imgur.com/5zEGz.png is what I want to get but with the numbers of each equations. – E.K Apr 1 '18 at 16:20
• As I said update your question with a full example. When people have to guess half your example they are much less inclined to help. – daleif Apr 1 '18 at 16:29
• your example should be a document that people can run to see the error, but gather can not possibly work interleaved with \item in that way, it is very hard to guess what you intend it to do??? – David Carlisle Apr 1 '18 at 16:33
• in gather environment had not to be items... – Zarko Apr 1 '18 at 16:42

Your question is not really understandable, the code fragment is not complete and the posted image appears to be showing unrelated text.

However this runs without error, the result is not really understandable though: it forms a strange mixture of bullet points and numbered equations, but hopefully you can edit it to make something usable.

\documentclass{article}

\usepackage{amsmath}

\begin{document}

\begin{itemize}
\item $c_t$: Consumption of a representative agent at period-$t$.
\item $l_t$: Labor of a representative agent at period-$t$.
$$E\biggl[\sum_{t=0}^{\infty}\beta^t U(c_t,l_t)\biggr]$$
with
$$U(c_t,l_t)=\theta\ln c_t+(1-\theta)\ln (1-l_t), 0<\theta<1.$$
\item $y$: Final Output.
\item $k=k_e+k_s$: Capital equipment and Structure.
\item $h$: Utilization rate of equipment.
\item $z$: Total Factor Productivity.
$$y=F(h k_e,k_s,l,z)=z(h k_e)^{\alpha_e} k_s^{\alpha_s} l^{(1-\alpha_e- \alpha_s)}, \quad 0<\alpha_e,\alpha_s,\alpha_e+\alpha_s<1$$
Production Technology.
\item $i=i_e+i_s$: Investment in equipment and structures.
\item $a=a_e+a_s$: Adjustment costs that can be used for
consumption,c,investment in structures and equipment.
$y=a+c+i_e+i_s$: Resource Constraints.\\
$k_s'=(1-\delta_s)k_s+i_s$, where $0<\delta<1$: The stock of structures
accumulation equation.
\item $q$: The current state of the technology for producing equipment.
$k_e'=(1-\delta_e(h))k_e+i_eq$:The equipment accumulation equation.
$$\delta_e(h)=\frac{b}{\omega}h^\omega, \omega>1$$
Equipment depreciation
function.
$$z_{t+1}=\gamma_z^{t+1}e^{\zeta_{t+1}}.$$
\end{itemize}
\end{document}