In MS-Word, Alignment determines the appearance and orientation of the edges of the paragraph:
In MS-Word, there is left-aligned text, right-aligned text, centered text, or justified text.
Align the text left or right.
Select the text that you want to align.
On the Home tab, in the Paragraph group, click Align Left or Align Right


Justify text

When you justify text in Word, you give your text straight edges on both sides of the paragraph. Justifying extends each line of your text to the left and right margins. Justifying text might make the last line of text in a paragraph considerably shorter than the other lines.
1.     Select the text you want to justify.
2.     On the Home tab, in the Paragraph group, click Justify .
Tips: 
  • In the Paragraph group, click the Dialog Box Launcher, and select the Alignment drop-down menu to set your justified text.

  • You can also use the keyboard shortcut, Ctrl + J to justify your text.