Solution:

1) file to reduce the file size. This will reduce the large image file in keynote to the adjusted small image file in keynote, and enlarge this image later, which will be weak. After shrinking, the file becomes 63.2M

2) When pasting, first save it as a png/jpg file, and then drag the saved file into keynote.

3) Export the keynote file as a pdf file. After export, the size is about 30M.

Extended data:

Another way to lose weight:

1) Because the currently used keynote is iwork version 09, the keynote file is a whole. After saving it as version 08, you can see the folders in keynote by "displaying the contents of the package".

2) Select all tiff files in the keynote folder and open them with the preview program. In the right column of the preview program, select all tiff files and save them as png files in a new folder. (Note that my 10.6.4 can be saved in batches, and yours should be. )

3) Delete all original tiff files and move png files in.

4) Double-click index.apxl.gz, drag the file to the "Text Editor" icon in the dock bar and open it with a text editor.

5) Replace all ". Tiff "and" png”。

6) Enter the command line and execute "gzip index.apxl" to recompress into a index.apxl.gz file.

7) Open in iWork '09 and save in 09 format.

In this way, my keynote file is reduced from 1 17M to 4 1.9M, which is 35% of the original.