3 mistakes learners make with suffixes and word building, each one named and explained.
Adding an ending often changes the root, so the word you started from is not always the word you finish with.
Discovery is written as 'discoverment' or 'discoverance'.
Ment and ance really do turn verbs into nouns, so applying one to a new verb is a sensible guess rather than a careless one.
Question. the noun from discover
A common answer. discoverment
The answer. discovery
Why. This verb takes y, the way deliver takes delivery.
The ending is not predictable. When in doubt, use the form you have actually read.
Explanation is written 'explaination', keeping the ai of explain.
The word it came from is right there in your head, and holding on to its spelling feels like the careful thing to do.
Question. explain, made into a noun
A common answer. explaination
The answer. explanation
Why. The root shortens when the ending is added, which is why it is not spelled like explain.
Some roots change when they take an ending. Learn the pair, not the rule.
Invisible is written 'invisable', or remarkable as 'remarkible'.
The two endings sound exactly the same in speech, so nothing you can hear separates them.
Question. invis___
A common answer. invisable
The answer. invisible
Why. What is left when the ending comes off is not a whole word, and those take ible.
Take the ending off. A word left standing takes able; a fragment takes ible.
WAJD spots these patterns in your child's answers and names the one behind their wrong answers, instead of just marking them wrong.