tu veux, il veut, nous voulons, vous voulez, ils veulent. But such irregularities apart, the principle is that nothing is removed from the stem. Consequently, verbs ending in -guer and -quer keep the -gu- or -qu- throughout the conjugation, even where simplifying this combination to -g- or -c- would be consistent with the rules of French orthography: Naviguer: nous naviguons, je naviguais, en naviguant… Provoquer: nous provoquons, je provoquais, en provoquant… Adding to the stem to preserve the pronunciation But although things are generally not removed from the stem, it is permissible to add letters when this is necessary. Certain stems can undergo various orthographic changes (which are not strictly speaking considered to be irregularities) in order to retain the correct pronunciation: The -c- in certain stems receives a cedilla before any ending which would otherwise change its pronunciation: Avancer: j'avance, nous avançons, j'avançais… Apercevoir: j'aperçois, tu aperçus, nous apercevons… The -g- in certain stems is followed by a silent -e- before any ending which would otherwise change its pronunciation: Manger: je mange, nous mangeons, je mangeais, vous mangiez, en mangeant… Endings (terminaisons) The ending is a suffix which tells us:a For all verbs, the mood and the tense; For finite verbs, the person and the number; and For the past participle alone, the gender and the number. Apart from a few frequent verbs which are considered totally irregular (mainly avoir, être, aller and faire), for each tense of each mood a series of six endings (one for each person singular and plural) is associated with a group or subgroup of verbs. Each of these series must now remain fixed throughout a single tense. Consequently, no ending may be modified even when orthographical simplification would be possible: For example, when the verb stem ends in a vowel (crier, fuir, tuer, voir, etc.), the -e- of the ending may become silent but must still be written (in the present, future, and conditional): Fuir (to flee), present subjunctive: que je fuie, que tu fuies, qu'il fuie, que nous fuyions, que vous fuyiez, qu'ils fuient… Créer (to create), future indicative: je créerai, tu créeras, il créera, nous créerons, vous créerez, ils créeront… Similarly, the imperfect indicative and present subjunctive endings for the first and second persons plural are -ions et -iez: for verbs such as gagner, voir, rire, briller, etc., the -i- of these endings must be retained, even though some speakers pronounce