| Trap, trapping, trapped | Track, tracking, tracked |
Why is the final consonant in trap doubled before ing or ed is added?
The final consonant in track is not doubled because track ends with two consonants.
| Pin, pinning | Pine, pining |
Pine drops the silent e because the tendency in English is to drop endings that are not needed for pronunciation before adding a suffix beginning with a vowel.
Form the participles of the following verbs:
| knot | rob | flop | |
| note | robe | elope | |
| deal | swim | quit | (u is not here a vowel) |
| clap | strike | crawl | (w is here a vowel) |
| stop | oil | wax | (x equals cks) |
| peal | rush | bow | (w is here a vowel) |
Exercise 37
Exercise 36 applies also to words of more than one syllable accented on the last syllable, if they retain the accent on the same syllable after the suffix is added. Thus we have
Rule 5.—Monosyllables or words accented on the last syllable, ending in a single consonant preceded by a single vowel, double the final consonant before adding a suffix beginning with a vowel.