when/by the time/before/until

[curious]

What is the difference between these sentences? What does "by the time" mean? How does it differ from when, before and especially until?

1- When I came to the USA, I had learnt some English.

2- By the time I came to the USA, I had learnt some English.

3- Before I came to the USA, I had learnt some English.

4- Until I came to the USA, I had learnt some English.

[Tdol]

1-3 are fine, but 4 doesn't work. There's not much difference between them, but 2 suggests that the learning came later in your life than the others.

[Nanatuha]

In curiosity. 4 just doesn't fit with the context? Or grammatically wrong?
I suppose it's former. This "until" suggests there would be a change thereafter, and in this sentence it means he/she quitted his/her learning despite from the situation that he/she likely to need english. So this sentence sounds odd. In other words, the sentence could be valid if there is a hint of why he/she quitted it. Am I right?
"Until I came to the USA, I had learnt some English. However I soon found that my native tongue is being accepted widely there and the fact I wouldn't have much troubles in daily life even without english." or something.

[matilda]

dear curious
1-when... means ( first i went to USA, and then, I learned English.)
2-by the time... means (I started learning English before going to USA, and when i arrived there, I was able to speak English.)
3-Before... means(when i started learning English, I didn't have any plan to go to USA, And when i arrived there, I was able to do whatever I want with my English.)
4- sorry, i have nothing to say. I'm not even sure if it is correct or not.

hope that helps

Matilda

[Tdol]

Nanatuha, you would be more likely to find something like 'Until I came to the USA, I hadn't learned any English'.

[Nanatuha]

Well, I understand this example sounds more natural.

I just a bit worried. Because this sentence didn't look a definite mistake to me, probably following sentence would be different though, I wondered if there was any grammatical mistake that I didn't notice.

Anyway, thank you tdol, for sparing your time. (Not only this topic)

[Casiopea]

In addition, with "until" there's an affirmative/negative relationship, like this,

EX: I was brave until I saw the bear. <affirmative "was">

Meaning: The moment I saw the bear, I was not brave, or I stopped being brave. <negative "was not" and "stopped being brave">

Here's the opposite meaning:

EX: I was not brave until I saw the bear. <negative "was not">

Meaning: The moment I saw the bear, I was brave or I became brave. <affirmative "was" and "became brave">

Now let's look at variations for our sentence 4.

Variation #1
I hadn't learnt English until I came to the USA. <negative "had not">

Meaning: The moment I came to the USA, I began to learn English. <affirmative "began to learn">

Variation #2
I had learnt some English until (that is) I came to the USA. <affirmative "had learnt">
Meaning: The moment I came to the USA, I stopped learning English. <negative "stopped learning">

Our sentence 4 Meaning: same as variation #2
Until I came to the USA, I had learnt some English. awkward given the ordering.

Try more context,

Sam: Your English is wonderful!
Max: Thanks. It wasn't until I came to the USA that I had learnt some English.

Hope that helps.

[Nanatuha]

I see. My vague understanding became considerably clear.

By the way, it seems I've hijacked this thread. My bad, curious.

[curious]

I see. My vague understanding became considerably clear.
By the way, it seems I've hijacked this thread. My bad, curious.

Feel free to do so.

My bad , curious.

[curious]

Variation #2
I had learnt some English until (that is) I came to the USA. <affirmative "had learnt">
Meaning: The moment I came to the USA, I stopped learning English. <negative "stopped learning">

Accoring to this, my 4th sentence is not wrong?

And I wanna learn one more thing. Does "when" version imply that I have not learned any English before coming to the USA, unlike the others (that is, before, by the time versions)?

What does "by the time" mean? Is it the same thing as "when" or "before"? Or if not, in what way does it differ from "when", "before" or "until"? Thanks.