上下标，分数：
\begin{equation}
f_{i}(x+e_{i} \Delta x,t+ \Delta t)=- \frac1\tau [f_{i}(x,t)-f_{i}^{eq}(x+e_{i}(x,t)]
\end{equation}大写罗马字母：
\uppercase\expandafter{\romannumeral 5 }点乘：
\begin{equation}
f_{i}^{eq}(x,t)=\rho \omega_{i} [1+3 e_{i} \cdot u + \frac92 (e_{i} \cdot u)^2-\frac32 u \cdot u]
\end{equation}连加：
\begin{equation}
\rho = \sum\limits_{i=0}^{n-1}f_{i} , \bm{ u} = - \frac1\rho\sum\limits_{i=0}^{n-1}f_{i}e_{i}
\end{equation}插入图片：
\begin{figure}[H]
\centering
\includegraphics[height=1in]{fig1.png}
\caption{$D_{2}Q_{9}$ lattice model}
\end{figure}多行分段函数：
\begin{equation}
e_{i} = c \begin{pmatrix} 0&1&0&-1&0&1&-1&-1&1\\ 0&0&1&0&-1&1&1&-1&-1 \end{pmatrix}~~~~~
\end{equation}算法伪代码：
\par
Here is the algorithm for solving 3D WSS:
%算法开始%
\begin{algorithm}[h]
\caption{Algorithm of calculate WSS}
\begin{algorithmic}[1]
\State $d \gets \alpha ,\beta, \gamma$
\State $q \gets 19$
\State $C \gets -1/(1-2\tau)$
\For{$d = 0 \to 2$}
\State $sumd\gets 0$
\For{$ i = 0 \to q-1$}
\State $sum\gamma\gets 0$
\For{$\gamma = 0 \to 2$}
\State $sum\gamma \gets sum\gamma+ e_{i\gamma}n_{d}n_{\beta}$
\EndFor
\State $sum\beta\gets 0$
\For{$\beta = 0 \to 2$}
\State $sum\beta \gets sum\beta+e_{i\beta}n_{\beta}(e_{id}-sum\gamma)$
\EndFor
\State $f_{i}^{neq} \gets f_{i}-f_{\i}^{eq}$
\State $sumi \gets sumi + f_{i}^{neq}\cdot sum\beta$
\EndFor
\State $\tau_{d}\gets C\cdot sumi$
\EndFor
\State $ WSS\gets \left | \tau \right | $
\label{code:recentEnd}
\end{algorithmic}
\end{algorithm}
%算法结束%求偏导：
\begin{equation}
\tau=\mu\frac{\partial v} {\partial r}, v=-kr^2+V_{max},
\tau_{max}=2\mu \frac {V_{max}}{R}
\end{equation}字体加粗：
$\bm{Step1}$特殊字符：
\ding{176} 
字符：
