微外教-72 | 外教教你条件句和IF句的时态怎么用？

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How many verb tenses can you count in the following sentences? "If you practice every day, you will improve. But you also need to know that if you didn't develop good study habits in the past, you might have trouble in the future." There are several verb tenses in this excerpt, and they are all mixed together. But complex sentences like these are what make English a very rich and interesting language. In this challenging lesson, we will look at conditional sentences that mix tenses and even use the verb "will" in the "if" clause.

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Transcript

Hi again. Welcome to www.engvid.com. I'm Adam. Today's lesson is a little bit tricky. It's grammar, it's conditionals, but we're going to look at "Mixed Conditionals". Now, before I get into the different types of ways that you can mix tenses and the conditionals, I want to do a very quick review of the conditionals that most of you learn in your ESL classes or your English... Other English classes, because these are the ones that are most commonly taught, and everybody, all your teachers want you to memorize these structures. The problem is then you might see mixed conditionals in other places, and you get all confused. Okay? I'm not going to get too deep into these, because you can find other good lessons by other engVid teachers who have already covered some of these on the site. I'm just going to do a quick review, and then I'll get into... Deeper into the mixed conditionals.

So here are the four main types of conditionals you learn: "If I won the lottery, I'd buy a house." So this, just so we are clear, is "would", I've contracted it to "I'd". "If I won", I have simple past tense, plus "would" in the second clause, in the condition clause, in the result clause. "If I had known she was coming, I'd have come too." Okay? Here I have the past perfect, plus "would have" plus PP, past participle verb. Now, these are both unreal, mean... Meaning that they are hypothetical, they are imaginary. This is about a future or present unreal situation. I didn't win the lottery, I'm not buying a house; this is all just imagination. This is about the past. Now, the reason it is unreal is because I can't go and change the past. So, this didn't happen, and so this didn't happen. This is, again, imagination, but we're looking at the past. Okay?

"If you boil water, it evaporates." If you notice here, I have simple present verb and simple present verb. This is a real conditional. It means it's true. Whenever you have a fact-okay?-a result is based on this condition and it's always true... By the way, "evaporates" means becomes steam, it goes away. Right? If you boil water, eventually you have no more water in the pot. So this is a real conditional, always true. Simple present, simple present. Lastly: "If you study hard, you will pass the test." Simple present verb, "will", verb, like future. So, again, this is a real situation, because this is true. If you do this, this will happen as a result. So these are the ones that you mostly learn.

If you have any questions, again, go to www.engvid.com, find the lessons about these that can explain it in more detail. But now we're going to see other situations, other sentences with "if" conditionals that are not like these. Sometimes we can mix tenses, sometimes you can... Sorry. Let me stop myself, here. Sometimes your teachers tell you: "Never put 'will' with the 'if' clause." Well, what I'm going to show you is that sometimes, yeah, you can. This is the problem with English: There's always exceptions to the rules. Today we're going to look at some of those exceptions. Okay? Let's see what happens.

Okay. So now we're going to look at a few different types of mixtures, if you want to call it that, with the "if" clauses. But before I start to show you these examples, I want you to understand that these mixed conditionals are all about context. You can generally understand what is going on, what the relationship between the two verbs are by looking at the context, looking at the time, looking at the place, looking at the situation that's going on, and should... It usually should be very clear, but in case you're wondering how to construct these so you can use them yourselves, I'll show you with a few examples. Okay? These are in no particular order. They're just examples, and we're going to look at them individually.

"If you didn't study computers in high school, you might find this course difficult." So now you're thinking: "Okay, here I have a simple past. Okay? And here I have a future. Well, that's a little bit confusing. Oh, how can you mix past and future?" But what you have to realize is that this is a past situation that if you didn't complete something, if you didn't study computers, when you... You're starting a new course today, and this course is going to be very difficult for you because you don't have the previous knowledge. So, a past situation has a present result. Okay? So one of the things you also need to think about mixed conditionals: A lot of it is a relationship between condition and result, as opposed to a condition and something happening depending on that condition. Okay? So this doesn't depend on this; this is a result of this. I'm not sure if that's exactly clear. 

When you say: "If you study hard, you will pass the test." You will pass the test... Your passing depends on what you did before. This doesn't depend on this. You can still do well, you can still find the course easy if you didn't study hard, but there's a possibility that this situation will have this result. Okay? So, simple past with future. And I use "might", "might" generally talks about the future. I could use "will" as well with this. So this is one example of a mixed conditional. And again, in context, you understand that the person is starting this course now without the background information, so it should be pretty clear. Let's look at the next example. "If you didn't want to buy that shirt, you shouldn't have (bought it)." Like, normally, we would end the sentence here, but just so you understand the complete idea. "If you didn't want to", past. 

When we're talking about a specific situation, we're talking about the time that you bought this shirt, so it's a simple past because it's a definite past time. And "shouldn't have", again, "you should not have bought it", it's a present perfect about an indefinite time, which is a little bit of a weird mix because in... That's you talking about your experience. When we're using the present perfect, we're talking about the experience, here, we're talking about a specific action happening in the past. Why did you buy it? Maybe somebody talked you into it. Okay? You didn't really want to, but you did. But you shouldn't have bought it. Okay? That should have been the experience that you had, but it wasn't. So, again, it's not necessarily a condition, here, it's just the relationship between two ideas. One doesn't depend on the other. 

Okay. Simple past, again, and "should not have", and again, in present perfect. Okay. Let's go to the other one. "If you go, I'll go too." Now you're thinking: "Well, no, it's not a mixed. Right?" Because I have a simple present, and I have the "will", future. But what you have to understand is that here, this is being used as a future. Okay? We're using the simple present tense to talk about the future. "If you go to the party next week, I will go too." Okay? So, future, future. Okay? Now, another thing: real, real, real. None of these are imaginary. Okay? All of this is actual real situations; we're not imagining anything. So, future with simple present and future with "will". Next: "If I had won the competition, I'd have a great job now." So here we have, again, the present... Sorry, we have the past perfect. Okay? And now, it should be: "I would have", plus another verb, a past participle, a PP verb, right? But here I have only "would have". "I would have", this is the main verb. This is not the "would have done", not the "have" of the whole mix. 

Right? This is its own verb. If you want, I'll give you another one: "I'd land a great job now". "Land" means get. It's another way to say... When you get a job, you land a good job. So why am I using the two mixes, here? "If I had won the competition", so there was a competition in the past, I'm going to that situation. If I had won it... This is a past unreal, because I didn't win it, then now I would have this job. But because this didn't happen, this is no longer a real situation. Okay? I didn't win the competition, so now I don't have a great job now. Okay? So you've got past, and you have hypothetical, and you have present time. So all these things are mixed, but again, it's all about context. What you have to understand: "If I had won, but I didn't, I would have, but I don't." Okay? So this is the whole idea of mixing conditionals and getting the idea across, without having a very set expression. It's all about the big idea, the relationship between the two. Okay? We're going to look at a few more examples. 

Okay, now we have a few more. Some of these are very exceptional, means you're not going to hear them too often; they're specific situations. The first one, as an example. "If you will please follow me, I'll show you to your table." Or: "If you would, please follow... If you would, follow me please, I'll show you to your table." This is not a conditional. This is just an expression, a very formal expression. You go to a restaurant, a very fancy restaurant. The host checks your name on the reservations. "Very good. If you will please follow me, I'll show you to your table." It's just a polite way to say: "Please follow me." Okay? And I'm using "if" plus "will", or "if" plus "would", and "will" in the second one. Okay? It's not a conditional. It means: "Please come this way." Okay. It's a very specific situation. You're not going to use this too often. "If it will help my case, I'll take the test." 

Now, here, I have: "If" and "will", and then "will" again. Now, you've always been told: "No, don't do that." Right? Don't put "will" with the "if" clause, but again, this is not a conditional. This is the result, this is what I will do to get this result. Okay? This does not depend on this. For example: The police... Sorry. The police arrested me, and they said: "We think you killed Mr. X and Mr. Y." I say: "No, I didn't do it." And they said: "Well, I think... We think you're lying." And my lawyer says: "Take the polygraph test." You know, like the test they put on you, and if you're lying, the machine goes up and down like crazy. So I say: "Okay, you know what? If it will help my case, I will take the test." If I can get this result, I will do this action. Okay? So the relationship is not of... One of condition and not of dependency. Result and action. 

Okay? But: "If it helps, I'll take the test." Here, we have the regular conditional. If it helps, this is what I will do. So if I want, for this condition, I'll do this action. Okay? Now: "If I knew how to cook, I'd have made you dinner instead." So last week, I took a girl out on a date, we went to a restaurant, the food was terrible. She thought, you know, maybe I'm not such a good guy, she doesn't want to date me again. And I say: "No, no, no. I'm a very good guy. I took you to a restaurant because I don't know how to cook. If I knew how to cook,"-unreal, imaginary-"I would have taken you to dinner last week instead." Right? So, past. "I would have made", so past situation, "would have made", but with an unreal condition, with an unreal situation now. "If I knew how to cook". I don't know how to cook, but I still want to tell you what I would have done in the past. 

Okay? So it's a little bit of a mixed, simple past with "would have made". Last one: "If I weren't so busy, I would go with you." If I weren't so busy, but I am very busy now, I would go with you. So because this is the situation: "If I weren't so busy," -it's real, I am busy-"I would go with you." Now it's a hypothetical. Now it's unreal because I can't go with you. Why? Because I'm so busy. "If my parents weren't going away next weekend, I would have invited you yesterday." Okay? So now, again, we're mixing. I'm still using the past, but I'm talking about the future, and I'm talking about what I would have done yesterday if this weren't true about next weekend. Okay? So, again, all you need to realize is that the verbs don't necessarily tell you what's going on in terms of time, especially when you have adverb clauses. It's not only with this. It sometimes happens with other adverb clauses, but especially with "if" it's confusing, again, because you're mostly being taught those first four that I showed you the... At the beginning. Okay? You can mix them. This is a past verb, talking about the future. 

Okay? The situation right now is that my parents are going away. But yesterday when I spoke to you, I didn't invite you because I know they're going. But if they weren't going, I would have invited you yesterday. Okay? I know it's a little bit confusing, but you may want to watch the video a couple more times. Please ask me questions in the forum at www.engvid.com; I will be happy to answer all your questions. There is a quiz, go try it out, see how you do with that. Of course, subscribe to my YouTube channel, and... If you like. And come back again and we'll do this again. Thanks.

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