LaTeXの記事で正当な位置合わせをする方法は？

Question

私はLaTeXで初心者です。私はいくつかの例を試しましたが、私は完全な正当な整列を行うことはできません。たぶん、この質問はあまり迷惑ではなく、あなたが手伝ってくれるかもしれません。私のコード例があり

：

\documentclass[10pt,a4paper]{article} 
    \usepackage[utf8]{inputenc} 
    \usepackage[L7x]{fontenc} 
    \usepackage[lithuanian]{babel} 
    \usepackage{multicol} 
    \usepackage[left=1.5cm,right=1.5cm,top=2cm,bottom=2cm]{geometry} 

    \begin{document} 
    \title{text text text text text text text text text text text text} 
    \author {text text text text} 
    \date{} 
    \maketitle 
    \center{\textit{ text text text text text text}} 
    \center{\textit{ text text text text text text}}\\ 
    \small\textbf{Abstract.} 
    An abstract is a brief summary of a research article, thesis, review, conference proceeding or any in-depth analysis of a particular subject or discipline, and is often used to help the reader quickly ascertain the paper's purpose. When used, an abstract always appears at the beginning of a manuscript or typescript, acting as the point-of-entry for any given academic paper or patent application. Abstracting and indexing services for various academic disciplines are aimed at compiling a body of literature for that particular subject. 
    \begin{multicols}{2} 
    \section*{\large Preface} 
    Academic literature uses the abstract to succinctly communicate complex research. An abstract may act as a stand-alone entity instead of a full paper. As such, an abstract is used by many organizations as the basis for selecting research that is proposed for presentation in the form of a poster, platform/oral presentation or workshop presentation at an academic conference. Most literature database search engines index only abstracts rather than providing the entire text of the paper. Full texts of scientific papers must often be purchased because of copyright and/or publisher fees and therefore the abstract is a significant selling point for the reprint or electronic form of the full text. 
    \section*{\large Some theory} 
    An abstract allows one to sift through copious amounts of papers for ones in which the researcher can have more confidence that they will be relevant to his or her research. Once papers are chosen based on the abstract, they must be read carefully to be evaluated for relevance. It is commonly surmised that one must not base reference citations on the abstract alone, but the entire merits of a paper.\\ 
    \end{multicols} 
    \end{document} 

は、事前にありがとうございます。

Answer 1

この

\center{\textit{ text text text text text text}} 

がそれを行うには正しい方法ではありません。この\ centerは、eintireドキュメントに対して有効です。 （これは\ raggedrightまたは\ raggedleftの場合もあります）グローバルアラインメントを何か他のものに設定した後、正当なアラインメントに戻る方法はありません。

ブラケットを\中央タグ...

{\center\textit{ text text text text text text}} 

（これは、しかし、あなたはテキストがそこに集中するでしょうがページの中央にだけ左側にあるボックスにセンタリングしたいテキストを入れないだろうしています）。あなたはおそらく何をしたいのか行うにはきれいな方法は、（{センター} beginと\エンド{センター} \）

\begin{center}\textit{ text text text text text text}\end{center}