Hi there! 

So sounding natural is all about confidence, it doesn't really matter if you've got an accent or not. Just like what <a ui-sref="user({id:comment.commenter_obj.id})" href="https://www.italki.com/user/600649">Nanren888- 新西兰</a> was saying about shortening the pronunciations of words, merging 2 words together in a sense; this will demonstrate flair and fluency, because you're so comfortable with the English language, you're able to talk in 'text script' and still understand what you're saying. It's like in French, they do something called Verlan, where they reverse words or small phrases, because they're so confident with their language, they'll know others will understand too. Of course, it's important to completely master the basics before you attempt to do this, but once you have, you'll have the rhythm of a native English speaker in no time.

I would judge a spoken English level by the grammar really...the more complex vocabulary can come later, but it's the little things such as 'it's a lovely day', when describing the day, rather than 'is a lovely day'..of course it depends on context.

As well, the best advice I can give you if you want to sound truly native is to practice, practice, practice (and preferable live in a country where they speak english, or live with people that are native English speakers). You have to really listen to how natives speak...everyone is different, it's impossible to say an exact way in which a native English speaker talks (you have English, American, Australian etc.) so it really depends on what kind of English YOU like and then taking the time to learn from that. 

Hope this helps! 

@JCccc

Well, I don't know how to judge someone's English speaking abilities, but if you ask me, the pronunciation, accent, choice of words and phrases etc would say a lot about someone's level in English. 

I think <a ui-sref="user({id:comment.commenter_obj.id})" href="https://www.italki.com/user/3922948" style="background-color: rgb(255, 255, 255);">Emily</a> has listed most of it.

English seems to be a language with many words, with subtly different meanings. There are words that are correct to use. There are words that are better, more descriptive to use. There are words that are clever or insightful to use.

So there are levels fo English ability, including within native speakers.

Beyond  mistakes in grammar, beyond appropriate words, through well-chosen words to word choices to be celebrated, there are levels.

Generally, I've found one main indicator is the presence of "u" for "you", "wanna" for "want to", confusions of "your", "you're" "there" "their" and such is one good indicator.

Beyond that it gets more difficult to tell. When you can look at it and say "Yes, there were many options, but that's exactly the right word to use". then you have something.

Sorry, not an easy test to do.

If you actually want to judge someone, you could try asking them. For example, when they say something, you could ask whether they can say that again in a different way. This can be tough, but someone who is proficient can usually find a few different ways to say similar things in English and tell you the subtle differences between them. Some of us, native or not, are simply lost for words sometimes though, so be kind about it. :)

Emily tried to imrpove on Sulochana's comment, but I fear it needs even more of a restructure.

Hey @Emily that sentence is definitely not grammatically correct and hard to follow. Anyway so would you mind sharing your thoughts on my question? Thanks. 

@ Sulochana

To learn the English language, first you have to listen more and learn ways of expressing your  thoughts without grammatical mistakes "will make u speak fluent as a foreign language"??!!