Highlight text by using the easy-to-use highlight tool or the text tools.
Use the Highlight tool to add a colored highlight over text. Use the Underline tool to put colored underlining or strike-through on text.
HIGHLIGHT TOOL
Method One: 
- From the Popular or Annotate category, select the Highlight 
 tool on the toolbar.
 - Click the drop-down arrow and choose between Text Highlight or Freehand Highlight. 
- Text Highlight: automatically recognizes text, and highlights them neatly.
 - Freehand Highlight: follows the way your cursor is dragged. This works well with scanned images.

 
 - Select your desired color and opacity from the menu button.

 - Drag your cursor along the text you want to highlight.

 
Method Two:
- Click the Select 
 option on the toolbar.
 - Drag the cursor over your selected text. Then, select from the Highlight, Underline, Squiggly, or Strikeout tools in the toolbar that appears under the selected text.
 

UNDERLINE TOOL
Method One:
- From the Annotate category, select the Underline 
 tool on the toolbar.
 - Select the text tool you want:
- Underline 

 - Squiggly underline 

 - Strikeout 


 
 - Underline 
 - Drag your cursor along the text you want to highlight with an underline, squiggly, or strikeout (see examples below).
 
Method Two:
- Click the Select 
 option on the toolbar.
 - Drag the cursor over your selected text. Then, select from the Highlight, Underline, Squiggly, or Strikeout tools in the toolbar that appears under the selected text. 

 
Edit your highlight:
- Click on your highlight and then a toolbar and two blue dots at the start and the end of your highlight will appear.

 - Drag the blue end dots to adjust (add/remove) the highlighted text.
 - Use the toolbar to comment, change the style (color/opacity), delete, or hyperlink the highlight.
 
Note: Text tools do not work in a .jpeg or .png (image) document. To underline texts on images, use the line from the Shape tool.
Note: You can easily view all the annotations and comments on a document through the comments history section. 

- Click on a listed highlight in the Panel to add a comment to the highlight.
 - Click on a listed highlight in the Panel, then click the three dots that appear on the right to Edit (add a comment), Delete (deleting it in the panel will also delete it from the document), or Export it (will automatically download as a text file).

 
Tip: You can select the Highlight and other text tools using keyboard shortcuts.
| Squiggly  
  | 
G | 
| Strikeout  
  | 
K | 
| Highlight  
  | 
H | 
| Underline  | 
U |