The whole world should switch to the metric system.

Before taking up the main subject, I notice you I'm a Korean, not an American. My country also uses metric system. But, because I want to be the champion of debate on the world, I am practicing debates now. So, I don't care my current shoes are now. I chose shoes of cons because I think this way can provide me fun and stimulate. And, I gift you my counterattacks several times so I will take win of this debate. I hope you also show me your whole cards included your hidden cards. First, I was not arguing that most of the world uses the imperial system. But I can admit my arguments could also maybe understood you like the means, so I admit this is my mistake. But, as I have mentioned before, my nation uses metric system so if my nation change standard from metric system to imperial system, I can also tell you changing standards of measurements in Korea from metric system to imperial system also costs a lot of expense, so my country must remain metric system because of my logics in Round 1. Second, I point out the problems of your examples. A)GENERAL USE "General conversation talking to people from the USA it is usually bothersome to have to explain that when you weigh, say 83 kilograms that that is about 185 pounds." But that bothersome is not a serious problem. They can easily calculate their weigh by using books, internet and other things from imperial system to metric system and the opposite also can be easily realized the same way. Do you really think this is a hard task? And, do you really think this bothersome is more great than the trouble in the USA by changing standard from imperial system to metric system? In addition, if a world with a single system would not need bothersome of translation so whole world should choose metric system without an exception, because of the same reason, "Every country in the world should unified one language because a world with a single system of language would not need bothersome of translation" can also be justified. You can say this analogy is a missed things so I guess now you can point out these things. (1)Language is not a unit like metric system. (2)English is not widely used like metric system, and it is not scientific reason to choose English to the standard of the world conversation. (3)I also agree to "Every country should choose one language. So my logic have no contradiction" Finally, I don't think the bothersome of measurements can be compared to the bothersome from different language. So, I have you a question again. Do you really think imperial system of measurements must be vanished from national standard? B)SCIENTIFIC USE Your examples also show partially things only. Also their are a few mistakes from trouble because of standards of measurement, in the most situation from the view of reverse, USA have no specific trouble to use imperial system to the experiments of scientific purpose. Mistake can be provoked everywhere. If The persons in charge of your examples are not missed their mission, the accidents was not happened. I think the main reason of the accidents in your examples is the carelessness of theirs. What makes you think the standards of measurements is the main reason to the accidents in your examples? In addition, when USA start to change from imperial system to metric system while many experiments and works still achieved like the current situation of USA, do you really think more complexity and mistakes that can provoke accidents like your examples will not be happened? Current age is not like 1889. Finally, you still argue scientific and logical reason, I have you a question. What make you think metric system have scientific and logical reason? Because it is based on scientific phenomenon? Widely used around the world? Being chosen by scientists? Or anything else? I already mentioned "We already know the centimeter's of our feet, we can easily use the arbitrary objects and calculations can be easily finished.", "It can much cheaper and easier to use than ruler. In addition, ruler in the market also have some error. We can say only the standards based on physical principles are only exact. But in our real world, the "physical principles" cannot be easily realized. It is expensive and hard to use. I can say it is also illogical." with this aspects. I'll wait your reply.