1. Adjust all at once: click Menu Command File → Page Setup. Click the document grid tab, as shown in figure 1. Select "No Grid" and click the "OK" button.

Tip: This method can easily adjust the line spacing of the whole document without any operation on the formula itself, which is very simple.

2. Local adjustment method: If you only want to adjust the line spacing of some contents in the main article, you can follow the following steps: select the line to be operated, click the menu command format → paragraph to open the paragraph dialog box; Click the Indentation and Spacing tab and adjust the spacing between "before paragraph" and "after paragraph" to "0 lines"; Remove the small tick in front of "If the document grid is defined, align the grid", as shown in Figure 2, and finally click the "OK" button.