This rule doesn't apply to envoyer and derivatives (See Conjugate voir and envoyer in Le Futur (future tense))
ESSAYER (to try)
Verbs in -AYER, in spoken French (included written dialogue in a play for example) also accept an alternative version where the y is kept (and also pronounced differently):
Here are more examples:
Common -AYER / -OYER / -UYER verbs
payer (to pay)
employer (to use/employ)
se noyer (to drown)
nettoyer (to clean)
essuyer (to wipe)
s'ennuyer (to be/get bored)
Examples and resources
Q&A Forum 4 questions, 7 answers
Bonjour Marnie !
Merci pour cette excellente suggestion, les exemples ont à présent été changés :)
Bonne journée !
La difference est beaucoup plus claire maintenant!
In the example in which they sweep the floor before we come, why is it nous ne venions instead of nous venions? Why is ne there?
this use of "ne" is called ne-explétif. It doesn't carry any negative meaning. It is there for emphasis. For it to be negative you would need its accompanying "pas" (or any other of its brethren).
There are several lessons offered on kwiziq on this topic. You can search on the library.
Greetings, -- Chris (not a native speaker).