You probably know this feeling already.
You can say the sentence. The grammar is fine. But it still doesn’t sound right.
Not wrong — just slightly off.
And nine times out of ten, it’s not your English. It’s whether the situation calls for casual or formal language
cas·u·al /ˈkaZH(o͞o)əl/ – designed for informal use; relaxed and unconcerned
for·mal /ˈfôrməl/ – based on conventional rules; suitable for important situations or occasions
Knowing the difference matters because English speakers switch between casual and formal constantly — often without realizing it. We don’t speak the same way to friends, coworkers, clients, doctors, or strangers. When ESL speakers use the wrong level for the situation, it can sound awkward, distant, or overly stiff — even when the grammar is perfect.
Introduction
This blog post is about casual and formal language, but the words “casual” and “formal” can also describe other things like clothing, an outing or event, a friendship or relationship, a meeting, etc
For example, casual dress might be jeans, a tee-shirt, and sandals as opposed to formal attire of a button-down shirt, tie, and pants for a male or a skirt and blouse/dress with closed toe shoes (for a female). An informal outing or event could be a parade, picnic, hike or bike ride, whereas a formal one would be a wedding in a church/synagogue/mosque, an anniversary party at a 5-star restaurant, or a ballet/opera at a fancy performance center.
A casual friendship or relationship is characterized by someone you have known for a long time, maybe someone from school, the neighborhood or a close relative as opposed to a formal relationship which might be a superior in your business, a member of a prestigious club, or a distant relative or acquaintance. A casual meeting might be just to offer ideas or to build cohesion or unity. It may take place in a casual setting, too, like an outdoor café, park or sporting event. A formal meeting might be to discuss something really important like the direction of the company or the unveiling of a new product, classes you need to complete a major or degree, or a talk with the doctor about an illness. It may take place in a boardroom, manager’s office, large auditorium, or another formal location.
You probably use different words, phrases, and ways of speaking in your native language when you are with your friends, family, other relatives, and people who are similar to you in age and personality (that’s casual or informal language). However, you have another set of words and expressions when you are in other situations like at work, when speaking with those people you may not know as well, or when you speak to those in authoritative positions (that’s formal language). Well, the same is true when you speak English.
You need to know casual English because you want to be able to understand and communicate with English speakers in everyday situations (by osinyemi). Likewise, you need to know formal English because you want to be able to read a book, give a business presentation, or write an official letter.
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Casual (Informal) Language
Casual language is used a lot around those you know well. It is a carefree way of speaking and one in which those who know you can easily understand or relate to. There are many slang expressions used in everyday conversations and these phrases change over time. With the explosion into the technological era leading to more frequent conversations, more and more slang words are added each day to the English language. It is also appropriate to use casual language when writing blogs, tweets, and advertisements. You may use casual language when you want to get to know someone on a more personal level or you want the person to feel at ease.

Formal Language
Formal language eloquently combines appropriate grammar and phrases to provide credibility for what is being said. For example, more formal language is routinely used in a professional setting (on a business trip or at a meeting), at certain places in a city (a church/synagogue/mosque, bank, library, high-end department store, government building), and in specific situations (job interview, dinner party, prestigious ceremony, or when speaking respectfully to a superior). You also use formal language in academic papers and official documents and speeches, books, news reports, articles and business letters. You may tend to use more formal language if you want to stress a point or convey authority or when you need to be strict.
Suggested Tips – When to Say What?
In doubt of which words to use? Here are some tips that can help you. If you listen and observe others in conversation, you will be able to tell what type of communication matches the situation. Or you can see how a person speaks to you; if he/she chooses to use more casual English, then it is appropriate for you to do so in return. You can also think of patterns. If you have spoken a certain way before under similar conditions or heard someone else speak in this situation, then it is most likely that you can talk this way here, too.
Casual or Formal Settings – What to Say When?
Just as casual English would be inappropriate in more formal settings, formal English would sound out of place to your friends or acquaintances that your friends introduce you to. For example, take a simple greeting. In a more formal greeting it is appropriate for you to say, “How do you do?” and “Nice to meet you” and to address the people you are meeting with the correct title of Mr./Mrs./Ms., Dr., Rev., etc. With those you know well, you probably say “Hi”, “Hey, What’s up?” or “How’s it going?”
When you are eating, it is important to remember your manners, especially during a business luncheon or meeting. You should politely ask for items to be passed to you like, “Could you please pass the coffee?” If you are eating with friends, you can be more relaxed with your manners and eating habits. “Hey, pass the coffee.” But, you would never say, “I’m starving” or, “I got a bad case of the munchies” in a formal situation, but with friends these are common phrases when you are hungry. You also would never say, “I don’t like (the food item’s) taste” in a formal setting, but with your friends it is acceptable to tell the awful truth about how bad the food tastes.
Let’s pretend you are in a dinner party and you need to leave for an urgent phone call. If you were eating with your future mother-in-law, you might say, “Would you please excuse me for a moment?” or “Excuse me”. However, with friends, you might say, “One sec” or “I’ll be back.” So, you leave the table and answer your phone call; if it’s your customer or boss, you could begin with, “Good Evening, how are you doing tonight?” But if it were your close friend you might say, “What’s good with you, my brother from another mother!”
Using Casual and Formal English
Maybe you have heard some of these more popular US casual English words/phrases:
Casual – Formal
Cuz – Because
Chill/chillin’- Relax/relaxing
Gonna – Going to
Sick – Great; amazing
Lame – Not good; worthless
Shoot me an email – Send me an email
Kickback – Move slowly; rest; relax
Fam – Family
Hold on – Wait
Gotta – Have to/need to
I’m outta here – I need to leave now
Guy/guys – You all; all of you; you
Besties – Best friends
Sucks – Terrible or awful
Bring it on – I’m ready for it
My bad – (Admitting guilt over something)
Yea/Yeah – Yes
Nah/Naw – No
I dunno – I don’t know
Whatever – I really don’t know/You can decide/I don’t have a preference
These casual words are widely used with people you know and are more comfortable being with. However, in formal situations, the words should be avoided and the more formal word/phrase substituted.
How to Practice Casual Language
Now, let’s see where you can practice casual language. You can…
Importance of Casual Language
How to Practice Formal LanguageNow, let’s look at formal English. You can…
Importance of Formal English
Other Differences
Your Turn to Practice Informal – Formal English
Informal:Hi, How are ya?, How’s it going?, How ya doin’? Formal: Hello, Good Morning, Good Afternoon, Good Evening, Nice to meet you, (title)Informal (response): Not much, Not bad, How’s everything with you?, Can’t complain, How ‘bout you? Formal (response): How are you doing?, I hope everything is fine with you.
Informal: You know what ya need to do? You gotta… Formal: Would you please allow me to make a suggestion? I think it might be best to…
Informal: Cool! Sweet! Awesome! Oh, my god that’s great! Formal: That is wonderful news! That is terrific to hear! That really is quite impressive.
Informal: Bye!, See ya!, Catch ya’ later!, See you, guys!, I’m outta here!, Later y’all!, Take care now! Formal: Good-bye, Mr./Mrs./Dr./Rev. (last name and add something to show respect, appreciation or importance to the situation) like Good-bye, Dr. Taleon. Thank you for taking the time to talk with my mother and for being so helpful to us.
Informal: G’night!, Sleep tight! Formal: Good night, Mr./Mrs./Dr./Rev. (last name)*****
Don’t forget to read part II of ‘2 More Ways to Talk Casual and Formal in English‘ and part III ‘Casual Conversation in ESL – The Inside Scoop Part III‘


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Concluding Remarks
The English language is no different from other languages in that the choice of words matches the person and situation you are in. There are times that casual English is the better choice and there are other times when formal language should be used. As you become more familiar with the English language and the English-speaking culture, you will more clearly understand the differences of casual and formal words/phrases. With daily practice and revision, your communications (whether casual or formal) will become as natural as it is in your first language and your confidence will open exciting new opportunities for you.
Please write to me using the comment box below and let me know of any interesting casual/formal expressions that you have in your native language. Or share an example of a casual or formal English phrase and when you have used it. I would be most grateful to hear from you (formal)…Hey! That would really be cool to hear from you, ya’ know? (casual). Thank you, very much for your time (formal). Respects! (casual).
Not sure if it’s pronunciation, confidence, rhythm, or something else entirely?
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