这就是我所做的。
\begin{tabular}{ |c|c| }
\hline
Notation & Definition \\
\hline
$\Lambda$ & Birth rate \\
$\mu$ & Natural death rate \\
$\alpha$ & Rate of death due to COVID 19 \\
$\beta$ & Transmission rate \\
$\delta$ & Rate of vaccination \\
$\lambda$ & Vaccine efficiency \\
$\epsilon$ & Rate at which exposed become infectious \\
$\gamma$ & Rate of recovery \\
$\zeta$ & Rate at which newly vaccinated people gain full immunity \\
\hline
\end{tabular}
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\captionof{table}{Definition of symbols and notation}
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To begin we can define the following:```