1. there: used in speech after a noun to emphasize which person, thing, etc., you are referring to

2. there: used in speech after a noun to emphasize which person, thing, etc. you are referring to
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Q1: Do we have to use "etc.," or "etc." in the sentence?
Q2: In Webster Dictionary, 'there' is classified as an adjective. However, in Webster Learner's Dictionary, 'there' is classified as an adverb. It is strange. How come it is classified differently? For example in the following: Ask that man there. That clock there once belonged to my great-grandmother.

1. ~~> ... etc., you are ...

2. In both of those examples, you are reading forms of colloquial speech. Remember that English, like Japanese, Korean, German, etc., are living languages, and changes occur over time. Sometimes those changes are results of dialects and/or very casual use. Sometimes those changes are results of new ideas and things in our world. Consider how the word "chip" has changed and been added to over the past few decades.
https://www.onelook.com/?w=chip&ls=a
Just look at all the different meanings in the column at the right for that one word!

Thank you for your help.

Do you mean both are correct?

1. there: used in speech after a noun to emphasize which person, thing, etc., you are referring to

2. there: used in speech after a noun to emphasize which person, thing, etc. you are referring to

It seems that in a dictionary, 'etc.,' is used, and in another dictionary, 'etc.' is used. Why do we need to use "," after 'etc.'?

To answer your first question:

When using "etc." in a sentence, it is generally recommended to follow it with a comma. This is because "etc." is short for "et cetera," which means "and other things." The comma helps to separate "etc." from the rest of the sentence and signal to the reader that there are additional items that have been omitted. Therefore, in the sentence "used in speech after a noun to emphasize which person, thing, etc., you are referring to," it would be more appropriate to use "etc.," with a comma.

As for your second question:

The classification of words can sometimes vary depending on the dictionary or linguistic perspective. In the case of "there," its classification as an adjective or an adverb can be understood differently in different dictionaries.

In general, "there" is most commonly used as an adverb to indicate a location or position. For example, in the sentences "Ask that man there" and "That clock there once belonged to my great-grandmother," "there" is indicating a specific place or position.

However, it is also true that "there" can be classified as an adjective in some contexts, especially when it is used after a noun to emphasize which person, thing, etc., is being referred to. This usage is more common in spoken English.

It's important to remember that language can be complex, and certain words can have multiple functions and classifications depending on their usage. In this case, the variation in classification may be due to different perspectives or ways of analyzing language.