I love English and was once good enough to become an English teacher at a Japanese junior high school. However, that was in the past and since then my knowledge of English has been declining rapidly. So, as part of my language learning, I decided to submit some simple questions and comments about English language that are not easy for me (and that I should ask on HiNative or Quora) to Newgrounds. I am not an expert in English and may be making elementary mistakes, but thank you for your patience.

Of Which | English Is Not So Easy 4

A high school English teacher once told me, "For Japanese students, English as a subject is like science." Indeed, at my school, students who were good at science subjects tended to be good at English as well, but I did not like that idea because I thought it was too mechanical.

Indeed, there is a scientific aspect to language. For example, this is especially true when I am working on rearranging sentences according to the grammatical rules of English, as in a puzzle game.

1. That house with a flat roof is my uncle's.

2. That house whose roof is flat is my uncle's.

3. That house of which the roof is flat is my uncle's.

4. That house the roof of which is flat is my uncle's.

―綿貫陽『基礎からよく分かる英文法』、p.202

But even if it were possible to rearrange a single sentence so that it had the same grammatical meaning, I think the reality is that usually one of them is the way native speakers most often use them, and the rest are not grammatically incorrect but are not used very often in daily life. According to Prof. Watanuki, who wrote the book, the first example is the most natural, the second is a little unnatural in its use of "whose roof", and "of which" is rarely used today.

Then what about "in which"?

1. This is the restaurant in which I first met her.

2. This is the restaurant which I first met her in.

3. This is the restaurant that I first met her in.

4. This is the restaurant I first met her in.

―綿貫陽『基礎からよく分かる英文法』、p.200

According to the book, the first is still used today but sounds very polite or old fashioned, the second is grammatically correct but not often used, the third, "that … in," is relatively used, and the fourth, without "that", is the most common. However, in the English I have been exposed to, examples using the first "in which" are more frequent, and I do not recall ever seeing a sentence with a preposition like "in" placed at the end of a sentence (In German, sentences with prepositions at the end of sentences are relatively common). Is this because most of the English texts I have been exposed to are taken from papers and articles for the English proficiency test? Or has such language become extinct today?