The opposite of horizontal is vertical.
When describing writing that is vertical instead of horizontal, you can say:
Japanese characters can be written vertically as well as horizontally.
I hope that helps!
horizontal （横向き）の反対は、vertical（縦向き）です。
横向きではなく縦向きに書いてあることを表す時、このように言うことができます。
Japanese characters can be written vertically as well as horizontally.
参考になれば幸いです！
When writing in the uk it is done from left to right or across the way ( horizontal)
If writing/characters are written from top to bottom or up to down ( standing up) this is called vertical
the opposite of horizontal (across or left to right) is vertical (standing up/up to down)
Japanese writing can be written in both horizontal and vertical
>Straight-up writing.
>Perpendicular writing.
*************************
*straight-up and perpendicular both mean vertical. Horizontal is the opposite of vertical.
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This appears to be described in dictionaries as scripts written in 'vertical writing,' however, we would commonly describe texts of this kind as having been written, 'top to botton' as opposed to the norm in western cultures, which is 'left to right.'
"Paul, what is that you are reading? It seems to be some ancient Egyptian hieroglyphics?"
"Well-observed my learned friend. That is exactly what I'm reading.
The script reads top to bottom: "Having a wonderful weekend break. Wish you were here."
vertical writingなどと辞書では表現されます。
ただ、西洋のleft to rightに対して、一般的にはtop tp bottomと表現されることが多いです。
"Paul, what is that you are reading? It seems to be some ancient Egyptian hieroglyphics?"
ポール、君何読んでるの？古代エジプトの歴史書っぽいけど？
"Well-observed my learned friend. That is exactly what I'm reading. The script reads top to bottom: "Having a wonderful weekend break. Wish you were here."
よく観察しているな優等生、その通りさ。
これは縦書きでね、いい週末を、君がここにいないのが残念だ、という書いてあるんだ。
When text is written from top to bottom instead of left to right, it is known as vertical writing. Although, this is not a common phrase. We usually describe something vertical, as top to bottom.
For example:
"The text is written from top to bottom".
"The text is written straight up and down".
文章を左から右ではなく上から下に書くことは、"vertical writing"（縦書き）といいます。
ただ、あまり広く使われている言葉ではありません。大抵英語では、vertical（垂直）であるものを"top to bottom"と表します。
（例文）
"The text is written from top to bottom".
（文章が縦書きで書かれている）
"The text is written straight up and down".
（文章が縦書きで書かれている）
When you're trying to explain that a certain writing style is vertical, then you can use the phrases "vertical writing" or "top to bottom writing"; then you can say it in the following ways:
-Vertical writing
-Top to bottom writing
In a sentence, you can say something like: Japanese can be written both horizontally and vertically.
「縦書き」を表す場合、以下のフレーズが使えます：
Vertical writing
Top to bottom writing
（縦書。）
文中では、以下のように使えます：
Japanese can be written both horizontally and vertically.
（日本語は横書、縦書両方で書けます。）
文章：sentences, script, writing (どっちらでもいいです）
縦書：vertical script
横書き：horizontal writing.
例：縦書の国語から横書きの英語の授業に入るのが難しい。It's difficult to go from the vertical script in Japanese to the horizontal script in English class.
ご参考にしていただければ幸いです。
「縦書」が英語で「Vertical writing」か「Written vertically」といいます。
例文：
縦書きにする ー To write vertically / To write in vertical lines, from top to bottom.
日本の小説はだいたい縦書きです。 ー Most Japanese novels are vertically written.
因みに、「横書き」が「Horizontal writing」か「Written horizontally」となります。
参考になれば嬉しいです。
こんにちは、
英語で「縦書」と言いたいと下の英文を使います
・Writing from top to bottom （上から下へ横書き）
・Vertical writing
縦 = vertical
例えば、
彼の書き方は縦書です
He writes from top to bottom.
ご参考になれば幸いです
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