From all the countries that I've visited until now, Italy is the best.
From all the countries that I've visited until now とは「今まで行った国の中で」という意味です。そして、Italy is the best とは「イタリアが１番良かったです」を表します。
「なぜ」を聞かれたら、"Because it has a lot of beautiful scenery and world heritage sites."この英文は日本語にしたら「美しい絶景と世界遺産が沢山あるからです」になります。
Of all the countries I have visited, Italy is my favorite!
We can travel all over the world, experience different cuisines, cultures, and traditions and we might like it while we are there but when we look back at all the places we have seen, we can decide which country was the best for us.
We all have different reasons why a certain place becomes a favorite or the best, some people like old buildings (architecture), the exquisite food (cuisine), the history, the culture, or the traditions.
Italy is the best country I have visited out of all the countries I have been to.
Out of all the countries I visited, Italy is by far the best.
I prefer Italy out of all the countries I have visited.
There are many ways you can make this statement. The best way is to be very direct and state "Italy is the best country I have visited." This statement indicates that you have visited many countries and that you like Italy the most. You can also simply state that "Italy is the best place I've visited!" This is what I would use when speaking about my travels to my favorite country.
これはいろいろな言い方ができます。
一番良いのは単刀直入に、
"Italy is the best country I have visited."（イタリアは今まで行った中で一番良い国です）
と言うことです。この文は、話し手がそれまでにたくさんの国を訪れたことがあってその中で一番イタリアが好きなことを表します。
また、シンプルに次のように言うこともできます。
"Italy is the best place I've visited!"（イタリアは今まで行った中で一番の場所です）
これは、旅行で訪れるのが好きな国として言う場合に使えます。
Of all the countries I've visited, I like Italy the most.
Out of all the countries I've been to, I like Italy the best
When you want to explain that you have been to a number of countries but your favorite so far is Italy; then you may say this in the following ways:
-Of all the countries I've visited, I like Italy the most.
-Out of all the countries I've been to, I like Italy the best
「今までに行ったことのある国の中で、イタリアが一番気に入っている」と説明したいなら、次のように言えます。
-Of all the countries I've visited, I like Italy the most.（今まで行った国の中で、イタリアが一番気に入っている）
-Out of all the countries I've been to, I like Italy the best（今まで行った国の中で、イタリアが一番気に入っている）
I like Italy the best out of all the countries I've been to.
Italy was my favorite country out of all.
Italy was the most amazing country I've ever been to.
I like Italy the best out of all the countries I've been to. - The "best" means that it is the number 1 thing out of all.
Italy was my favorite country out of all. - The word "favorite" means the thing you like the most out of all the things.
Italy was the most amazing country I've ever been to. - You can use some adjectives like "amazing", "outstanding", "incredible", etc. to describe the country and then add the word "most" to say that it was the top ranking.
I like Italy the best out of all the countries I've been to.（今まで行った国の中でイタリアが一番好きです）
→"The best" は、それが全てのものの中でナンバーワンであることを表します。
Italy was my favorite country out of all.（イタリアが一番よかったです）
→"favorite" は一番好きなものを表します。
Italy was the most amazing country I've ever been to.（今まで行った国の中でイタリアが一番素晴らしかったです）
→"amazing" "outstanding" "incredible" などの形容詞を使ってその国を説明することもできます。そこに "most" を加えるとそれが一番であることを表せます。
I prefer ...(something over something else) Like...(object) most of all.
Out of all the countries I have visited...I prefer Italy. I like Italy the most.
Our preferences determine our choices...in almost all situations.
We all have personal likes and dislikes...And in this case, we are talking about a preference for one particular country over all others one has visited.
We might use prefer in any number of ways;-D
EG: I prefer tea to coffee. I prefer Jack to Jill...
I prefer Itay over every other country that I have traveled to...I like Italy most of all
ほぼ全ての状況において、人の行動を決めるのは好きか嫌いかです。
みんなそれぞれ好きなもの嫌いなものがあります...この場合は、今まで訪れた中で最も気に入った国について言っています。
"prefer" の使い道は無数にあります。
例：
I prefer tea to coffee.（コーヒーよりもお茶の方が好きです）
I prefer Jack to Jill.（ジルよりもジャックの方が好きです）
I prefer Itay over every other country that I have traveled to...I like Italy most of all
（今までに訪れたどの国よりもイタリアが好きです...イタリアが一番好きです）
Out of all the countries I've been to, Italy is my favourite
Italy is the best country I have visited!
When talking about what you think is the better thing you would say it is your 'favourite' although you can also say it was the 'best' as well
These sentences you have been to a few countries and you like Italy the most
アメリカ合衆国 
南アフリカ 
イギリス 
