SPELLING RULES FOR THE -ING FORM 

- With most verbs, we add -ing to the infinitive.

   see - seeing          watch - watching        buy - buying

- For verbs ending in -e, we remove the -e and add -ing.

  have - having        write - writing         save - saving

- For one-syllable verbs ending in a consonant+vowel+consonant, we double the consonant and add - ing.

  get - getting        run - running        shop - shopping