want to speak real english from your first lesson sign up for your free lifetime account at englishclass101.com hi everybody my name is alicia in this lesson i'm going to talk about the differences between must have to and should i'm also going to talk quickly about the negative forms i'm going to focus on comparing the very similar meanings of these words so let's get started first let's talk about must must in the negative we say must not so must or must not in british english you may hear mustn't mustn't but we don't really use this in american english we usually use must not when we want to use this pattern so we use must and must not first for official rules official rules means for example rules at a company or rules at a school rules at the airport police so law related rules like things that are related to your society so official rules we use must and must not to explain these rules for example passengers must show passports at immigration passengers must show passports at immigration this shows it's an official rule all passengers must show they have a responsibility it's the rule must expresses this it's a formal rule-like statement must not then visitors must not wear shoes inside visitors must not wear shoes inside so that means visitors must take their shoes off before coming inside so must not wear shoes inside means not allowed it is prohibited you may not it's not allowed so may not means it's like less formal than must not must not is much stronger i'm not going to cover may in this one so must not is more formal it sounds more rule like official rule-like the second use of must and must not is for strong personal advice strong is the key here i'm going to talk more about personal advice later in this lesson but when you want to express strong personal advice you can use must or must not for example like uh visiting a doctor's office or maybe some other kind of health related issue or something that's very important to someone's life you can use must and must not to express advice in those situations for example you must stop smoking you must stop smoking so this might be advice strong personal advice for a very heavy smoker someone who smokes a lot you must stop smoking or you'll die or you must stop smoking or you're going to get much more sick for example another one you must not forget to take this medicine you must not forget to take this medicine so that means you have a responsibility it's very important to take this medicine you must not forget to take this medicine so we use this for strong personal advice so strong is an important key word here we don't use must for like everyday general advice i will talk about that later so official rules strong personal advice this is how we use must and must not let's continue to the second point for this lesson which is have to in the negative don't have to uh for different subjects doesn't have to uh in the negative and in the positive has to the same rules will apply to need to as well need to also have got to in british english so let's look at how we use this we use have to and the negative don't have to to talk about responsibilities responsibilities so this can mean school responsibilities work responsibilities like relationship responsibilities family responsibilities the things that we have some kind of obligation to do so in many cases we don't want to do these things but there's some need there's some responsibility for example i have to go to work i have to go to work have to shows it's a responsibility i have to go to work she has to leave early she has to leave early she has a responsibility to leave early she has to so as i said when she or he or it is the subject we conjugate the verb we change the verb from have to has she has to leave early these show a responsibility of some kind so many learners ask like can i use must here i must go to work she must leave early it's not grammatically incorrect to say must i must go to work but because we use must for official rules and for like strong personal advice it sounds kind of strange to use must hear like i have to go to work that's an everyday regular responsibility when we make like a sentence like i must go to work it sounds like there's a very like strong reason or there's a very official reason i must go so you might hear that in movies like in epic big scale like fantasy stories there's someone fighting a war for example or there's someone with a really big responsibility they might say i must go in those cases and when they're using like an old style of english fine but in everyday english using i must before some of like your responsibilities sounds pretty strange so i don't recommend it in most cases if you want to sound funny you can say something like i must go to work but in most cases i would not recommend it i have to go to work sounds much more natural or she must go or she must leave early it sounds way too formal so please use has to or have to to talk about your everyday responsibilities now let's look at negatives negatives so again don't have to is like the i subject version i don't have to we don't have to they don't have to if your subject is he she or it it becomes doesn't have to he doesn't have to she doesn't have to so examples he doesn't have to come he doesn't have to come this means he has no responsibility to come it's okay he doesn't have to come no responsibility he can but he doesn't have to that's what this communicates he doesn't have to come same thing here we don't have to leave yet so yet shows it's okay now we don't have to leave yet maybe later later we don't have to leave yet again we can but we don't have to there's no responsibility there so an important point about the negative with have to uh or need to is that when you make a negative with this pattern make sure you're talking about a common or irregular responsibility we use these patterns we use this have to this negative have to pattern for things that we can reasonably be expected to have a responsibility to do so an example i have heard from students from learners is something like this i don't have to drink alcohol at work i don't have to drink alcohol at work so for grammar this sentence is correct the sentence is grammatically perfect there's no communication problem it's a great sentence but this sounds strange because for most people drinking alcohol at work is not a regular responsibility i mean unless unless you're like a bartender or you're someone who works with alcohol like a wine sommelier whatever but for most people in this example drinking alcohol at work is not a regular responsibility so it sounds a little strange to say i don't have to drink alcohol at work we typically we often regularly use have to in the negative i don't have to to talk about our everyday responsibilities so like i don't have to get up early on the weekends means i have no responsibility to do that on the weekends or if you have a holiday i don't have to go to work today that's a much more common way of using don't have to so please keep this point in mind make sure you're expressing a regular like a reasonable expectation when you use the negative form here okay so with that in mind let's continue to the last point for this lesson the last point is about should should in the negative it's should not and we reduce should not to shouldn't shouldn't should should not and shouldn't we use should and should not for general advice general advice this means every day uh just regular life advice so compare this to must and must not which we use for very strong personal advice in most cases in everyday life we use should to talk about general advice a suggestion a recommendation we use should to talk about that we do not use must to talk about that unless for some reason it's very very strong examples you should go home you should go home maybe you look sick you should go home or he should take a day off he should take a day off maybe he looks stressed so using must in these cases would sound strange because these are kind of everyday small suggestions like you must go home that sounds very serious or he must take a day off again sounds very serious why did something happen so use should in these cases also using have to in these cases kind of sounds a little strange too if i use have to here you have to go home you have to go home like why do i have a responsibility to go home it's kind of strange same thing here he has to take a day off why like maybe there's some company rule he has to take a day off i don't know but be careful make sure if you're giving just advice your opinion just use should of course there are some cases where you can use have to in place of should to make a stronger recommendation this is useful when you're giving like a restaurant recommendation and it sounds like this you have to try this restaurant so that sounds more like excited than you should you should try this restaurant and you have to try this restaurant have to sound stronger because it's like you're saying you have a responsibility to try this restaurant you have to try this restaurant or you have to try this recipe it sounds a little stronger than you should so you can use it in that way but if you're giving advice like based on something you can see or if you're trying to give someone like career advice maybe be careful with your use of should and have to so have to shows like you're putting responsibility on that person so should is more like general advice okay let's look then at using shouldn't shouldn't so as i said should not reduces to shouldn't shouldn't we shouldn't talk so loudly we shouldn't talk so loudly so in this case we shouldn't that's like advice for our group maybe we're talking very loudly and one person says oh no we shouldn't talk so loudly so that's giving advice to the group we should talk more quietly so we shouldn't talk so loudly another one she shouldn't worry so much she shouldn't worry so much so it's general advice don't worry so much is another way to say that she shouldn't worry so much so again using something like must not sounds way too serious here like we must not talk so loudly it's for strong personal advice so using must hear sounds very strange same thing here she must not worry so much again very strange because this is a very strong sounding expression she must not worry so much similarly using have to here we don't have to talk so loudly that expresses lack of responsibility we don't have to talk so loudly but we can is kind of the idea there so this doesn't sound natural same here she doesn't have to worry so much this could be used perhaps she doesn't have to worry so much like you could say in for example a work situation you have a colleague a co-worker and she worries a lot and you want to express to your manager or to your team member she doesn't have to worry so much i can do it like in that case maybe it's natural but if you're giving general advice shouldn't sounds much better so keep this in mind should and should not for your general everyday advice for recommendations have to and don't have to for your responsibilities must and must not for official rules and for very strong personal advice so i hope that this introduction to these three expressions helps you understand the differences and the different feelings and situations in which we use these so if you have any questions or comments or if you want to practice making some sentences with these please feel free to do so in the comment section of this video of course if you liked this lesson please don't forget to give it a thumbs up subscribe to our channel if you haven't already and check us out at englishclass101.com for some other things that can help you with your english studies thanks very much for watching this lesson and i will see you again soon bye bye [Music] you