Lesson 15c: Variations
| Keyword | Root | Plural | Past | LY | ING | R |
| groan | groan | groans | groaned | groaning | groaner | |
| frog | frog | frogs | ||||
| grog | grog | grogier | ||||
| broke | broke | |||||
| crone | crone | crones | ||||
| drone | drone | droned | droning | |||
| crop | crop | crops | ||||
| drop | drop | drops | dropped | dropping | ||
| cross | cross | crosses | crossed | crossing | ||
| drove | drive | drives | drove | driving | driver | |
| grove | grove | groves | ||||
| drub | drub | |||||
| grub | grub | grubs | grubbed | grubbing | ||
| drug | drug | drugs | drugged | drugging | ||
| drum | drum | drums | drummed | drumming | drummer | |
| crab | crab | crabs | crabbed | crabbing | crabber | |
| drab | drab | |||||
| grab | grab | grabs | grabbed | grabbing | grabber | |
| brace | brace | braces | braced | bracing | bracer | |
| grace | grace | graces | graced | gracing | ||
| grade | grade | grades | graded | grading | grader | |
| brag | brag | brags | bragged | bragging | bragger | |
| crag | crag | cragged | ||||
| drag | drag | drags | dragged | dragging | dragger | |
| braid | braid | braids | braided | braiding | braider | |
| frail | frail | frailly | frailer |