I Miss You in Chinese / Japanese...

我想你 is the Chinese way to say “I miss you.”

It is said in the same word order in both English and Chinese.

思戀 is a term used for when you miss a lover.

It suggests that you are separated (not by choice) and have longed for each other. It's a strong feeling of missing your lover.

一日千秋 is a Japanese and Chinese proverb about missing someone.

一日千秋 is often used to express how hard it is to wait for someone's return or to be away from someone.

Some will translate this as “one day feels like a very long time” or “waiting for someone (something) is hard.”

You might see this romanized as a single word, Ichijitsusenshuu, or as “Ichijitsu Senshuu” from Japanese.
If you break down the characters one-by-one, we get:
一 = one/a
日 = day/sun (can also represent time or date)
千 = 1000/thousand
秋 = autumn/fall

Together, 千秋 can mean “autumn comes thousand times” (or 1000 years). It can also be read as 1000 periods of time.
However, it relays the idea of heartache as you wait for someone you miss.

獨自 is a Japanese word that means “alone” in the context of a person by himself/herself.

This can be translated as individual, solo, on one's own, or by oneself.

獨自一人 means “alone” in the context of a person by himself/herself.

煢煢孑立形影相吊 is a Chinese proverb about the state of being as alone as you possibly can be.

It can be translated as “Alone with only your shadow for comfort/company.”

戀しがる is the most common Japanese verb for missing someone or yearning for someone (it could also be missing a place).

戀しがる is the shortest way to say, “I miss you” or “I yearn for you” in Japanese.

Breaking down the characters:
恋し (koishi) yearned for; longed for; missed (acts as an adjective in Japanese).
がる (garu) to feel, behavior (this represents emotion and turns the whole word into a verb in Japanese).

Note: Because this selection contains some special Japanese Hiragana characters, it should be written by a Japanese calligrapher.

孤獨 means lonely, solitude, loneliness, and lonesome.
In some contexts, it can mean reclusive, isolated, single, or solo.

孤獨 is a Japanese word but not a good selection for a wall scroll.
In Chinese, this will relay a rather sad feeling to anyone who reads this calligraphy on your wall.

The version shown to the left is the Traditional Chinese and ancient Japanese version. In modern Japan and China they often use a different more simplified version of the second character (as shown to the right). If you want this Japanese/Simplified version, please click on the character shown to the right instead of the button above.