How to fix "Underfull \hbox (badness 10000)" warning? - latex

Question

I have this small .tex file.
\documentclass{article}
\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{titling}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{tikz}
\setlength{\droptitle}{-3.5cm}
\setlength{\parindent}{0cm}
\newcommand{\squad}{\hspace{0.5em}}
\author{vladgovor77771}
\title{Some article}
\begin{document}
\maketitle
\textbf{Task 1} \newline
Task description: \newline
\end{document}
When compiling, it warns about line
\textbf{Task 1} \newline
With the following message:
"Underfull \hbox (badness 10000)".
How do I fix this?

Answer 1

I had a similar issue, I solved it by removing any \newline or \\ at the and of every sentence that had nothing textual below.
For instance, two examples that causes that problem:
An example. \\
This is well used. \\
This line will cause the error. \\
(I'm a new paragraph) \\
Because there's nothing directly underneath.\\
The last line does NOT require a "newline".
This is a thid paragraph. \\
:D
The same is true for figures or similar
This is a line.
Putting a "newline", as here, before a \begin will cause the error. \\
\begin{figure}[h]
....
\end{figure}

Answer 2

A quick and nice solution is to use package parskip, and instead of using \newline or \\ for line breaks, simply insert an empty line
\documentclass{article}
\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{titling}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{tikz}
\usepackage{parskip} %% <-- added
\setlength{\droptitle}{-3.5cm}
\setlength{\parindent}{0cm}
\newcommand{\squad}{\hspace{0.5em}}
\author{vladgovor77771}
\title{Some article}
\begin{document}
\maketitle
\textbf{Task 1}
Task description:
\end{document}
The warning will be gone.
By the way, to know why it happened, refer to this question on TeX Stack Exchange.

Answer 3

Instead of forcing an underfull box with \newline, you could simply leave an empty line to start a new paragraph:
\documentclass{article}
\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{titling}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{tikz}
\setlength{\droptitle}{-3.5cm}
\setlength{\parindent}{0cm}
\newcommand{\squad}{\hspace{0.5em}}
\author{vladgovor77771}
\title{Some article}
\begin{document}
\maketitle
\textbf{Task 1}
Task description:
blabla
\end{document}