E R Spelling Change Verbs, Part 1-
We will now look at a few E R verbs that have spelling changes in their stem. A couple of examples are manger (to eat), and commencer (to begin).
While the verb manger is in most ways quite regular, in the first person plural (nous) of the present tense, we must remember to place an e before the o n s ending in order to preserve the soft g sound. I eat-is je mange, but we eat-is nous mangeons. The same is true for all other verbs whose infinitive ends in g e r. Here are a few more examples: déranger (to disturb), juger (to judge), nager (to swim), partager (to share), ranger (to arrange, put in order), songer (to dream), and voyager (to travel).
The verb commencer is an example of a group of spelling change verbs whose infinitive ends in c e r. Except for the first person plural of the present tense, a few forms of the Imperfect tense, and the nous form of the Imperative, this verb is regular. The French say je commence, but notice their use of a ç before the o n s ending in nous commençons. This is done to preserve the soft sound [s] because a c before an a, o, or u is a hard sound and is pronounced like a [k], whereas a c before an e or an i is soft and is pronounced like an [s]. However, if you place a cedilla under a c that precedes an a, o, or u, the ç becomes a soft sound and is pronounced like an [s]. You may have noticed the ç in the word français. It is there for the same reason. Other verbs conjugated like commencer include: prononcer (to pronounce), divorcer (to get a divorce), remplacer (to replace), and menacer (to threaten).