Come giustificare completamente l'allineamento dell'articolo LaTeX?

Question

Sono principiante in LaTeX. Ho provato alcuni esempi, ma non riesco a giustificare pienamente l'allineamento. Forse questa domanda non è molto fastidiosa e potresti aiutare.

c'è il mio esempio di codice:

\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} 

Grazie in anticipo.

Answer 1

Questo

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

non è il modo giusto per farlo. Questo \ center ha effetto per il documento eintire. (Questo sarebbe anche il caso con \ raggedright o \ raggedleft) Non c'è modo di tornare ad un allineamento giustificato una volta impostato l'allineamento globale a qualcos'altro (centro raggedright o raggedleft)

Si dovrebbe mettere le parentesi prima del \ tag centro ... che è

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

(questo non sarebbe però mettere il testo che si desidera centrare al centro della pagina, ma solo in una scatola nella parte sinistra se il testo verrà centrato in là). Il modo pulito di fare quello che probabilmente si vuole fare è quello di utilizzare l'ambiente centrale (\ begin {center} e \ end {center})

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