Quote:
I think there is a run on sentence in option B
An Asian vine that has grown rampantly in the southern United States =>"Asian vine"is the subject and "has" is a verb and it expresses a complete thought.
Since it was introduced in the 1920 for thwarting soil erosion => "it" is the subject which refers to Kudzu and "was" is the verb and it also expresses a complete thought
As EducationAisle notes, there's no run-on in (B), because "that has grown rampantly in the southern United States" isn't independent - it's a modifier describing the Asian vine. Take a simple example: "Dan,
who runs a mile in fifteen minutes, is not a great athlete." Here we do have two clauses, but the one in red functions as a modifier, and so it's not independent. In the
OG question, "that has grown" is part of a modifier describing the vine. If there's only one independent clause, we don't have a run-on.
Quote:
Even if we consider "Since" as a dependent marker and 2nd clause as dependent clause. What is the intent of the
OG Explanations "The adverbial Clause Since it was introduced in the 1920 should not be set off from has grown rampantly"
There are two ways to understand the
OG's point. First, if we have a long modifier, and
within this modifier we get additional information about when an action takes place, we typically won't use a comma between action and time-modifier.
For example, "My child,
who has been screaming since she awoke at 3AM, supposedly has many positive qualities." Notice that the blue component is one long modifier describing "my child," and there's no need, within the modifier, to separate the action ("has been screaming") from the description of when the action takes place ("since she awoke"). Similarly, in (C) "that has grown rampant in the southern United States since it was introduced in the 1920s to thwart soil erosion" is one long essential modifier describing the "Asian vine." "Since it was introduced" tells us when the rampant growth started.
Second, the word "since" is tricky because it has two meanings. In both the official question and in my example above, it means "from the time when." But it can also mean "because."
Watch what happens if I insert a comma before "since" in the previous example: "...who has been screaming, since she awoke at 3AM." Now it sounds as though the kid has been screaming
because she awoke at 3AM, rather than indicating the timeframe of her meltdown. The same thing happens in (B): "that has grown rampantly in the southern United States, since it was introduced in the 1920s." The growth happened because it was introduced in the 1920's? It makes sense to say that the 1920's marks the time
when growth became rampant; it makes less sense to claim that the plant has grown wildly
because it was introduced in this decade. So the version without the comma is more logical.
I hope that helps!
_________________