15. Can you say "this is a pencil and this is a mechanical pencil” in Japanese?

 15. Connecting Noun sentences with "N1 wa N2 de, N3 wa"

In Japanese, we use the structure "N1はN2で、N3は" to connect two noun sentences. By changing "desu/deshita" in the first sentence to "de," we can link them together.

これは鉛筆です。これはシャープペンです。
Kore wa enpitsu desu. Kore wa shāpupen desu.
→ これは鉛筆で、これはシャープペンです。
Kore wa enpitsu de, kore wa shāpupen desu.
This is a pencil, and this is a mechanical pencil.

わたしは大学生でした。彼は高校生でした。
Watashi wa daigakusē deshita. Kare wa kōkōsē
deshita.
→ わたしは大学生で、彼は高校生でした。
Watashi wa daigakusē de, kare wa kōkōsē deshita.
I was a university student, and he was a high school student.

When the sentences have the same subject, it is more natural for the first noun to give a general description of the subject rather than the second one. For instance, nationality is considered a broader description compared to a person's occupation. Therefore, changing the order of the two nouns is not natural.

[natural]
わたしは韓国人で大学生です。
watashi wa kankoku-jin de daigakusē desu.
I am Korean and a university student.

[unnatural]
わたしは大学生で、韓国人です。
watashi wa daigakusē de, kankoku-jin desu.
I am a university student and Korean.

Furthermore, this structure can be used to connect noun and verb sentences. The verb is used at the end of the sentences. Here's an example:

これは英語の教科書です。+ （わたしたちは）これを水曜日に使います。
Kore wa ēgo no kyōkasho desu. + (Watashitachi wa) kore o suiyōbi ni tsukaimasu.
→ これは英語の教科書で、水曜日に使います。
Kore wa ēgo no kyōkasho de, suiyōbi ni tsukaimasu.
This is an English textbook, and we use it on Wednesdays.

In summary, you have learned how to connect noun sentences using the examples provided. Keep in mind that this structure can also be used to connect a noun and a verb sentence, with the verb placed at the end.