How to use dashes to indicate turning points in sentences

How to use dashes to indicate turning points in sentences

It's not clear. Let's look at a few more examples
(1) in fact, that set of numbers is just a scratch on the spine of a book, which is a slight injury. It can be solved with a package of paper. Is it worth making a fuss? (Qin Wenjun's cell of a great man) (2) really, up to now, I really haven't had any good beans like that night, ——I don't see that night like drama any more. (Lu Xun's "she Xi") (3) with the wind blowing, the green waves turn up round by round. At this time, you will really admire the two words "Mai Lang" created by people in the past. If it's not a coincidence, Get excited over a little thing. What's the essence of the refined language? (Mao Dun's praise of white poplar) (4) "it's so hot today!" when do you go to Shanghai? "Zhang Qiang said to Wang who just entered the door." clear: the above four sentences all indicate the turning of the topic. "(1)" is it worth making a big surprise give advice and suggestions? " (2) in front of "I really didn't eat the good beans like that night", this means "beans". But suddenly, when it comes to "drama", the meaning has changed, which seems unreasonable. In fact, what the author wants readers to think about is that it's the interest of watching social drama that makes us remember eating beans, (3) in front of the dash, it says "green waves round by round", and then it turns to "admire the word" Mai Lang "made by the old people." this is a thought jump of empathy, which shows the author's extremely happy mood at the moment. (4) in front of the dash, the words are irritated and cursed by the hot weather, while the latter words suddenly turn to the question of Xiao Wang, So before and after the dash meaning constitutes a turning point
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