Remember that some verbs change their form in the -ing form.
In most verbs we add -ing to the infinitive form:
meet ⇒ meeting
talk ⇒ talking
work ⇒ working
When verbs end with -e we take away -e and add -ing:
have ⇒ having
use ⇒ using
write ⇒ writing
When verbs end in -ie we take away -ie and add -ying:
lie ⇒ lying
tie ⇒ tying
When one-syllable verbs end in a short vowel + consonant we double the consonant and add -ing:
hit ⇒ hitting
sit ⇒ sitting
put ⇒ putting
When verbs with more than one syllable end in a stressed short vowel and consonant (not y, w or x) we double the consonant and add -ing:
begin ⇒ beginning
forget ⇒ forgetting