First we open WPS Office 2019 and click the New button on the left, as shown in the picture below.

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We create a new blank ppt document, as shown in the picture below,

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After opening the ppt document, we click the insert tab above, as shown in the picture below,

In the ribbon, we find the audio and click to open it, as shown below,

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In In the drop-down list that opens, we select the background music we want to insert, as shown in the picture below.

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Find what you want in the My Computer folder Insert the background music, and then click to open, as shown in the picture below.

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Finally we can see that in the ppt slide, the insertion is successful. background music, as shown in the picture below,

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