Here's how I would go about it.

The steps:

• Click the View tab and in the Presentation Views group select Slide Master.
• Hover your mouse over the slide layouts on the left until you come to the Two Content Layout slide...then right-click it and select Duplicate Layout.
• The new layout slide is created below the original one and is currently selected.
• Right-click it and select Rename Layout.
• In the window that opens, give it a new name...like 4-Content Layout...and click Rename.
• With the new slide selected, on the slide itself in the middle of the screen click to select the content placeholder on the left side of the slide.
• Hold down the Control key on the keyboard and click the content placeholder on the right side of the slide.
• With both placeholders now selected and square handles now visible around them, click one of the handles at the bottom-center of one of the placeholders and drag it up to about half it original size...and release the mouse.
• With both placeholders still selected, press Control + C on the keyboard to copy...then press Control + V to paste another set of placeholders on the slide. (You could also right-click on one of the placeholder borders and choose Copy, then right-click in an open spot in the slide and choose Paste.)
• With the newly pasted placeholders still selected, click any border and drag them down to the emply space below the original ones.

You now have a 4-Content master slide. Click Close Master View on the ribbon...and on the Home tab, in the Slides group, click Layout. You should see your new layout listed. Click it to insert it into the current slide.

I hope that's the help you need. Good luck.
George