请查看下面的代码并帮助我。
\begin{longtable}{| c | L{3cm} | L{3cm} | L{3cm} | L{3cm} | L{3cm} | L{3cm} | L{3cm} | }
\hline
\rowcolor{Gainsboro!60}
\makecell{} & \makecell{Centrifugal \\ force} & \makecell{Gravitational \\ force} & \makecell{Inclination} & \makecell{Vibration} & \makecell{Fluidization} & \makecell{Inertial \\ force} & \makecell{Other \\ Effects}\\
\hline
\endhead
Size & \multirow{2}{*}{Cyclones} & Counter flow vertical air raise classifiers, Zig-Zag Classifiers & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & Cyclones, Rotating Wheel Air-Classifiers, High-Efficiency Separator, Turbo-air Classifier, Circulating air-classifiers. & & \\
\hline
Density & & alpha & echo & charlie & bravo & & \\
\hline
Shape & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & & \\
\hline
\end{longtable}
由于您上面的例子不可编译，因此我建议使用这个 MWE。从 \documentclass{...} 开始并定义一个\newcolumntype{L}。
\documentclass{article}
\usepackage{longtable}
\usepackage{makecell}
\usepackage{multirow}
\newcolumntype{L}[1]{>{\centering\arraybackslash}p{#1}}
\usepackage{lscape}
\begin{document}
\begin{landscape}
\begin{longtable}{| c | L{2cm} | L{2cm} | L{2cm} |L{2cm} | L{2cm} | p{2cm} | p{2cm} | }
\hline
% \rowcolor{Gainsboro!60}
\makecell{} & \makecell{Centrifugal \\ force} & \makecell{Gravitational \\ force} & \makecell{Inclination} & \makecell{Vibration} & \makecell{Fluidization} & \makecell{Inertial \\ force} & \makecell{Other \\ Effects}\\
\hline
\endhead
Size & \multirow{2}{*}{Cyclones} & Counter flow vertical air raise classifiers, Zig-Zag Classifiers & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & Cyclones, Rotating Wheel Air-Classifiers, High-Efficiency Separator, Turbo-air Classifier, Circulating air-classifiers. & & \\
\hline
Density & & alpha & echo & charlie & bravo & & \\
\hline
Shape & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document. & & \\
\hline
\end{longtable}
\end{landscape}
\end{document}
答案1
不清楚您的问题是什么（除了表格太宽，不适合页面）。您可以考虑对代码进行以下微小更改：
\documentclass{article}
\usepackage[margin=25mm]{geometry}
\usepackage{ragged2e}
\usepackage{longtable, makecell, multirow}
\newcolumntype{L}[1]{>{\RaggedRight\hspace{0pt}}p{#1}}
\usepackage[table, svgnames]{xcolor}
\begin{document}
\begingroup
\footnotesize
\setlength\tabcolsep{3pt}
\setlength\extrarowheight{2pt}
\begin{longtable}{| c | *{7}{L{20mm}|} }
\hline
\rowcolor{Gainsboro!60}
& \makecell{Centrifugal \\ force}
& \makecell{Gravitational \\ force}
& \makecell{Inclination}
& \makecell{Vibration}
& \makecell{Fluidization}
& \makecell{Inertial \\ force}
& \makecell{Other \\ Effects} \\
\hline
\endhead
% table body
Size & \multirow[t]{12}{=}{Cyclones}
& Counter flow vertical air raise classifiers, Zig-Zag Classifiers
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& Cyclones, Rotating Wheel Air-Classifiers, High-Efficiency Separator, Turbo-air Classifier, Circulating air-classifiers.
& & \\
\cline{1-1}\cline{3-6}
Density
& & \makecell{alpha}
& \makecell{echo}
& \makecell{charlie}
& \makecell{bravo}
& & \\
\hline
Shape
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kind of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& & \\
\hline
\end{longtable}
\endgroup
\end{document}
答案2
也许这就是你正在寻找的
我已经使用该booktabs包排版了此表。您的问题不太清楚，所以我只是尝试了我认为好的方法。
代码
\documentclass{article}
\usepackage{longtable}
\usepackage{makecell}
\usepackage{multirow}
\newcolumntype{L}[1]{>{\centering\arraybackslash}p{#1}}
\usepackage{lscape}
\usepackage{booktabs}
\usepackage{geometry}
\begin{document}
\begin{landscape}
\begin{longtable}{
c
>{\raggedright}p{2.5cm}
>{\raggedright}p{2.5cm}
>{\raggedright}p{2.5cm}
>{\raggedright}p{2.5cm}
>{\raggedright}p{2.5cm}
>{\raggedright}p{2.5cm}
p{2cm}}\toprule
& \multicolumn{3}{c}{\scshape force}
& Inclination
& Vibration
& Fluidization
& Other \\\cmidrule{2-4}
%
& \multicolumn{1}{c}{Centrifugal}
& \multicolumn{1}{c}{Gravitational}
& \multicolumn{1}{c}{Inertial}
&&&& Effects \\\midrule
%
Size
& \multicolumn{1}{c}{Cyclones}
& Counterflow vertical air raise classifiers, Zig-Zag Classifiers
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& Cyclones, Rotating Wheel Air-Classifiers, High-Efficiency Separator, Turbo-air Classifier, Circulating air-classifiers.
& & \\\cmidrule{1-1}\cmidrule{3-6}
Density
& & aplha
& echo
& charlie
& bravo
& & \\\midrule
Shape
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& These kinds of issues are mostly related to the PDF viewer, they will not appear in a print version of the document.
& & \\\bottomrule
\end{longtable}
\end{landscape}
\end{document}
提示：避免在表格中使用垂直线:)
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