英文的一問,進來!!!!!!

When there is only one vowel - a, e, i, o, u = ing running, getting, hitting travelling etc. There may be some exception too - knowing etc

two vowels are together, then simply add ing - sailing, eating, hearing etc.

You have to memorise it by heart. Then, you will know it gradually.

因為e同a都是響音( a e i o u)，你要記住凡是有兩個響音的話，就不用重複的。
例如 : see : seeing

just memorizes them.