Bonjour, comme expliqué dans les commentaires précédents, ces abréviations se trouvent surtout dans les sms et sur les réseaux sociaux, mais je trouve qu'avec les smartphones elles sont moins fréquentes qu'avant.  Je dirais que les plus fréquentes sont:

A+

ASV ? (sur les sites de chat en ligne)

auj

BCP (plus souvent en minuscule qu'en majuscule)

Bonjour (je pense que vous vouliez dire "bj" ?)

C

CAD

Ct

DSL (très souvent)

G (très souvent aussi)

Kel

slt

STP/SVP (très souvent, utilisé aussi à l'oral)

ya (utilisé à l'écrit comme à l'oral, en français parlé)

Hello,

I think it depends on how old are your friends, and what are their goals when learning English. Do they want to have a conversation ? Read in English ? Get by in English-speaking country ? Understand movies ?

How "beginners" are they? If they are beginners but know some English, this video course might help. There are two levels, 1 and 2 but each lesson gradually covers more topics:

https://learningenglish.voanews.com/a/lets-learn-english-lesson-one/3111026.html

It has video, the transcript for the video, vocabulary, and some grammar notes.

If they have never studied English before or don't know a lot, I think you should start with the basics, such as pronounciation, introducing oneself, talking about likes and dislikes, giving and asking for directions...

If they want to learn about basic grammar, I think this website looks good:

http://www.talkenglish.com/grammar/grammar.aspx

I read on the website NihongoShark that to progress in a language you need consistent, level-appropriate language exposure. I think you could help your friends find ressources in English online, like short stories for beginners, songs, children's cartoons (or for adult beginners)...

Don't worry, if you and your friends are motivated, you will manage ! Your friends can also join Italki to meet people and ask questions.

Best of luck. =)

Oui, c'est tout à fait possible. Il me semble que cela s'utilise surtout dans le cas d'un doute "moral", dans le sens où l'on se méfie de quelqu'un ou quelque chose et l'on ne souhaite pas s'engager. C'est une formule assez formelle. Voici deux exemples que j'ai trouvé sur le dictionnaire TLFI:

    a) Restriction, limitation à l'approbation ou à l'adhésion que l'on apporte à quelque chose. Faire, introduire des réserves; apporter une     réserve à qqc. J'apporte à Gide mon témoignage avant son départ (...) et si j'ai des réserves à faire (...) je les ferai lui présent (<font size="-2">DU BOS,</font>     Journal, 1925, p. 358). Tout en procédant au sous-répartement, l'assemblée peut, pour l'avenir, exprimer son opinion, produire ses     observations, faire des réserves (<font size="-2">BACQUIAS,</font> Cons. gén. et cons. arrondiss., 1934, p. 99).

"b) Doute, restriction sur le caractère ou la probité de quelqu'un. Émettre des réserves sur le compte de qqn, sur son honnêteté. [Ma mère] se faisait un scrupule (...) de risquer, en faisant quelques réserves sur la jeune fille avec laquelle je lui avais dit que j'allais me fiancer, d'assombrir ma vie (<font size="-2">PROUST,</font> Prisonn., 1922, p. 13)."

Hi,

If you really want to immerse yourself in a country's language I recommend finding a job in a country speaking your target language. I have done this last summer, and it was great ! I worked in Scotland at a hotel, room and board were deduced from my salary. I have tried to find similar ads and I found this:

http://www.transitionsabroad.com/listings/work/shortterm/france.shtml

You can find job offers in which you are paid/receive lodging in exchange for teaching English. In your free time, you can explore or you can save money for one month and travel during the other month. I have no idea what level of profiency you need, but I guess that for physica labor and teaching English, you don't need much. If you want to travel within France, I should warn you that right now there are strikes at the SNCF (trains) and Air France (flights). It should stop during summer.

You can also use Airbnb (stay with locals, and it's cheaper than a hotel's room !)

If you don't like hot weather, avoid the South of France and mountains.

I recommend visiting "Le Mont Saint Michel", it's a not-quite island in Normandie (North of France). It has a nice, old village and a there is an abbey on it. However it must be quite busy in the summer.

https://www.ot-montsaintmichel.com/en/visite-mont-saint-michel.htm

We have somthing curious in France ! try typing "Dune du Pilat" =)

To meet new people and save money, you can carpool with Blablacar

https://www.blablacar.fr/

There must be apps for this as well.

Most of the time, Ryanair offers cheap flights. There are two airports you can reach from Manchester, Bézier and Carcassone (South of France.

Hope this helps, have a nice trip ! =)