verbs with the sounds : [e] et [è] ou [é] et [ è]

In some verbs, you can hear in alternation : [e] or [è]
acheter : j'achète, nous achetons, j'achetais

other verbs : geler (congeler, dégeler), lever (enlever, relever), mener (amener, se démener,emmener, ramener).

Some other verbs have a similar alternation between: [é] and [ è]
céder: je cède, nous cédons / Test: listen to Charlotte

-c- and -g- ( sounds [s] and [j])

Certain stems can undergo orthographic changes (which are not, strictly speaking, to be considered as irregularities, because it's consistent with the rules of French orthography) in order to keep the same pronunciation.

sound [s]

The -c- becomes -ç- before -a-, -o-, -u- to keep the pronunciation [s]: [lans], [plas] etc...
lancer, placer
when you say : je [Ians], je [plas] / nous [lansI], nous [plasI]
you must write: je lanc-e, je plac-e, nous lanç-ons, nous plaç-ons
etc...

nous annonç-ons , j'annonç-ais / listen to Charlotte
( You can also do it with the name garçon -not garcon !- listen the difference)
apercevoir / aperçu

sound [j]

dégager, diriger
The -g- in certain stems becomes -ge- before -a-, -o-, -u- to keep the pronunciation [j] : [dégaj], [dirij] etc...
(it's the same for the name: cageot)
nous dégageons , je dégageais / listen to Charlotte

-yer verbs: sound [J]

In -yer verbs, the y ( son [J]) becomes an i for some persons :
"appuyer" [apViJé] :balayer, essayer, ennuyer, envoyer, payer , essuyer etc. ...

The sound [J] disapears when the letter "y" becomes an "i" with "je, tu, il et ils" :
j'appuie [apVi], je balaie [balè] , il envoie[ Bvwa], ils paient [pè]...
but: nous appuyons , vous payez etc...

It's easier to memorize the same rule for all the verbs in order to avoid some mistakes!
(the [J] is only tolerated for a few verbs, so you can hear: [jebalèJ], [jepèJ] , but it's not the best way to speak) ,, )

To hear Charlotte :

1 In "language", choose "french" ( Drop-down list), and Charlotte for "voice";

2 write or "Copy and stick" what you want to hear

3 clic on "say it" to hear Charlotte!