1. For the one-syllable words ending in single vowel + single consonant, double the consonant before a suffix beginning with vowel.

Examples:
• beg + ed = begged
• run + ed =running
• rob + er = robber
• sad + est =saddest

2. For the one-syllable words ending in a single vowel + a single consonant, double the consonant before a suffix beginning with a vowel.

Examples:
• beg + ed = begged
• run + ed =running
• rob + er = robber
• sad + est =saddest
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Which one is right? I added articles in #2.

I'd use #2.

Both #1 and #2 are stating the same rule for one-syllable words ending in a single vowel and a single consonant. In both cases, when adding a suffix that begins with a vowel to these words, you double the consonant before adding the suffix. The examples given in both #1 and #2 are the same and demonstrate this rule. So, either #1 or #2 can be considered correct.