Group 1 words are using the 'er' sound. Some words have er in the middle, some have them at the end.
Group 2 words are looking at using the suffixes er/ed/ing and you double the consonant before adding the suffix, e.g.
forget becomes forgetting (so you double the 't' before adding ing.
Suffixes are a group of letters we add on the end of a word to change the meaning of it.
Children are to write out the word in a sentence, underline it or write in a different colour, to show they understand what it means.
Group 2, don't forget you have the extra 10 words to learn and you will be tested on a random 2 on Friday.