IF / ELSE / END-IF - do I need periods or not?

Old code has periods everywhere. New examples use END-IF and almost no periods.

Which style should a beginner use? I keep breaking IF blocks.

Use explicit scope terminators: END-IF, END-READ, END-PERFORM. One period at the end of the paragraph is enough.

Periods inside IF logic are a classic way to accidentally end the IF early. That is why old code is scary.

Shop standard here bans periods except end of paragraph / sentence where required. Reviews catch it.