Normally, papers has to be prepared in two column mode. The following code will allow you the table across two columns.
\begin{center}
\begin{table*}[ht]
{\small
\hfill{}
\begin{tabular}{|l|l|c|c|c|c|c|c|c|}
\hline
\textbf{Hello}&\textbf{Hello}& \multicolumn{7}{|c|}{\textbf{Hello}}\\
\cline{3-9}
\hline
AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA\\
BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB\\
AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA&AAAAA\\
BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB&BBBBB\\
\hline
\end{tabular}}
\hfill{}
\caption{Table Name}
\label{tb:tablename}
\end{table*}
\end{center}
I copy their comments for those who has the same problem. @Thanks you, Chus”.@ 
Liz said that “This code produces a line spacing of 3 lines in my document. Is it possible to avoid that?”
Chus solved this problem by introducing the center environment inside the table environment.
