documentclass{article}
usepackage[utf8]{inputenc}
usepackage{tabularx}
usepackage{float}
RequirePackage[a4paper, left=2.5cm, right=2.5cm, bottom=2.5cm, top=2.5cm]{geometry}
usepackage[usenames, dvipsnames]{color}
usepackage[usenames,dvipsnames,svgnames,table]{xcolor}
usepackage{array,multirow,graphicx}
definecolor{lightgray}{rgb}{0.95,0.95,0.95}
RequirePackage{ragged2e}

begin{document}

renewcommand{arraystretch}{1.6}
newcolumntype{Y}{>{hsize=.7hsizeRaggedRightarraybackslash}X}
newcolumntype{a}{>{columncolor{lightgray}}Y}
newcolumntype{C}[1]{>{columncolor{lightgray}}p{#1}}

begin{table}[H]
    caption{XXXXXXXXXXXXXXXXXXXXXXX}
    begin{tabularx}{textwidth}{C{5mm}@{}a*{3}{Y}@{}}
        %% table header
        hline
        rowcolor{lightgray}multicolumn{2}{r@{}}{XXXXXX $rightarrow$} & multicolumn{3}{c@{}}{The content of the word} \
        rowcolor{lightgray}multicolumn{2}{l@{}}{$downarrow$ XXXXXX} & XXXXX & XXXXXX & XXXXX \ hline
        %% body of table
        &XXXXX & XXXXX & XXXX  & XXXXX \
        &XXXXX
         & XXXXX
         & XXXXX par XXXXXXXXXX
         & XXXX, par XXXX,par XXXX/XXXX,par XXXXX,par XXXXXX, etc. par \
        multirow{-3}{12mm}{rotatebox{90}{parbox{linewidth}{XXXXXXX}}} &XXXXXX XXXXX &  XXXXXXXX par sequence
         & XXXXXX
         & XXXXXX, par XXXXX, par XXXXX \     hline
    end{tabularx}
end{table}

end{document}

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[]OT1/cmr/m/n/10 XXXXXXX
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