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逗号和引入部分(introductory element)





hello grammarians paige and i are here to teach you about introductory elements in sentences and how commas relate to them Paige what how do we how should we define what an introductory element is so it's pretty much something that happens at the beginning of a sentence it can be like a dependent clause or an adverb but as we will see you soon it's something that is separated off with of course a comma because that's what commas do they are separators so let's talk about dependent clauses first let me just write out a sentence that begins with a dependent clause when you come in please take off your shoes and I've made the difference between the dependent clause and the independent clause pretty clear so this isn't you know the dependent clause is purple the independent clause is green is there a need for a comma here okay because we're leading with a dependent clause and that means that this thing can't stand on its own right it's like it's like the ladder up against the tree because an independent clause and green can stand on its own a dependent clause cannot so we need to differentiate it from the rest of the sentence by putting the comma there so this is a dependent clause and this is an independent clause so if you start a sentence with a dependent clause you're going to need to put the comma in the middle before you proceed to the independent clause which is the part that makes it an actual functioning sentence right if you have it the other way around though if it's just please take off your shoes when you come in no need for a comma I'll show you so I'm not sure why this is I I think it may just sort of be a style relic I'm not entirely certain I mean if you go back in American history and you look at like the Federalist Papers and you look at the way that people used commas in the 18th century it doesn't make a whole lot of sense relative to how we use commas today so a lot of this is cultural but I can tell you that when an independent clause comes before a dependent clause you don't use a comma and if you are uniting two independent clauses in the following sentence I wrote an elephant and then I ate a mango these two things are both independent clauses right I wrote an elephant then I ate a mango right like these these two things I need to be connected by this conjunction and but that's not all they also need to be joined by a comma now you could also sub out if you wanted to you know get rid of this comma in this end and put in a semicolon but that's a story for another time so if you're uniting two independent clauses just do comma and then a conjunction so that's one way to think about how to use commas for introductory elements like dependent and independent clauses but there's also another thing I want to introduce you to and that's sentence adverbs follow us over to the next screen so Paige what what is a sentence adverb how does it work so we've been talking about you know starting sentences with clauses but that doesn't always have to be the case you can start a sentence with an adverb like let's say initially I was afraid so what is initially doing in this sentence here in this expression basically it's modifying like the whole rest of the sentence it's modifying beat I was afraid so we're gonna put a comma here to separate it from the rest of that expression that's why we call it a sentence adverb cuz it's not this is not the same as saying I was initially afraid this is kind of like you said modifying the entire expression let's let's look at another example basically you're the greatest oh thanks Paige so we've got this word basically basically is modifying the entire expression it's kind of qualifying the whole thing so we're gonna put a comma between this sentence adverb and the sentence itself exactly cool so initially page this seems pretty complicated to me right but basically I think we got it down all right we think that essentially you can learn anything David out page out