I wonder how much colder it is in Hokkaido than in Tokyo.
I wonder how much colder it is in Hokkaido than in Tokyo.
→北海道って東京よりどれくらい寒いんだろう
比較級が使えると思います。
「colder」は「cold（寒い）」の比較級です。
この「wonder（動詞）」は「～だろうかと思う」という意味です。
回答は一例ですので、参考程度にしてください。
ありがとうございました
How much colder is it in Hokkaido compare to Tokyo?
Which is colder; Tokyo or Hokkaido?
When you want to find out which of the two places is colder; then you may ask in the following ways:
-How much colder is it in Hokkaido compare to Tokyo?
-Which is colder; Tokyo or Hokkaido?
この二つの場所のどちらがより寒いか確認したいなら、次のように言えます。
-How much colder is it in Hokkaido compare to Tokyo?（北海道は東京よりどれくらい寒いのですか）
-Which is colder; Tokyo or Hokkaido?（東京と北海道どちらがより寒いですか）
When asking the different between two places then we can say 'compared' to
Which is colder? lets the person know what information you want by adding 'Hokkaido or Tokyo?' they know what you are talking about being colder
二つのものの違いを確認するなら、'compared to'（～に比べて）が使えます。
'Which is colder?'（どっちがより寒い）は、何について知りたいのかを伝えます。
'Hokkaido or Tokyo?'（北海道か東京）は、'Which is colder?' が何についてなのかを伝えます。
What's the temperature difference between Hokkaido and Tokyo?
Is Hokkaido colder than Tokyo and if so by how much?
How much colder is Hokkaido than Tokyo?
By asking "what's the temperature difference" you are implying that you are already aware that Hokkaido is colder but you want to know by how many degrees.
If you are unaware as to which city is colder, you can ask "is Hokkaido colder than Tokyo." By adding "how much" at the end of the question, you will be provided with the degrees as well.
"How much colder" is a more casual way of saying "What is the temperature difference".
"what's the temperature difference"（気温の差はどれくらいですか？）と聞くことで、北海道は寒いことを知っているけれど、何度くらいの差なのかを知りたいことを表します。
もしどちらが寒いかを知らないなら、 "is Hokkaido colder than Tokyo." （北海道は東京より寒いですか？）と聞くことができます。 "how much" （どれくらい）を付け足すことで、何度くらいかを教えてくれることでしょう。
"How much colder"（どれくらい寒いですか？）は、よりカジュアルなフレーズで、気温差はどれくらいかという意味です。
"How much colder is Hokkaido compared to Tokyo?" You are specifically asking what the temperature difference is between the two places, if there is one.
"Is Hokkaido much colder than Tokyo?" This is a simple yes or no question and the answer will indicate which of the two is colder.
"Which place is colder, Hokkaido or Tokyo?" is another way to word the same question however the answer would be either Hokkaido or Tokyo, as opposed to yes or no.
"How much colder is Hokkaido compared to Tokyo?"
（東京と比べて、北海道はどれくらい寒いですか？）
これは、東京と北海道の気温の差が具体的にどれくらいあるかを聞くフレーズです。
"Is Hokkaido much colder than Tokyo?"
（北海道は東京よりずっと寒いですか？）
これは、はい、いいえで答えるシンプルな質問です。
"Which place is colder, Hokkaido or Tokyo?"
（北海道と東京ではどちらが寒いですか？）
これは、上のはい、いいえで答える質問にたいして、北海道、東京どちらかが答えになる質問です。
In terms of temperature, what's the difference between Tokyo and Hokkaido?
When talking about temperature differences, you want to ask how different the cold is when comparing Tokyo and Hokkaido. The first suggestion above is a closed question, assuming some prior knowledge. The second example is an open question.
By starting the question with the word' how' I am using a word that asks the quality or meaning of something. In this case it is the weather that I want to find out about. Using the word 'compared' I am asking for the person to give me a comparison of the weather in the two places Tokyo and Hokkaido. To compare the two the places the other person will tell me about the differences and similarities of the weather in the two places. By asking' how cold is it' I am specifically asking for a comparison of the temperature of the two places.
how'は、ある物の様子を聞くのに使われる言葉です。この場合、天気です。
'compared'は、東京と北海道2つの場所を比べるのに使われる言葉です。2つの場所を比べることで、相手は天気のよく似ているところ、違うところを教えてくれるでしょう。 I am asking for the person to give me a comparison of the weather in the two places Tokyo and Hokkaido.
' how cold is it'（どれくらい寒いですか？）は、2つの場所の温度を比べる質問です。
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