はじめに

英語で科学的な内容を説明することは、英語学習者にとって大きなチャレンジの一つです。今回は、「半導体（semiconductor）」に関する英文を例に、どのように自然で正確な表現へと改善していけるかを見ていきます。

原文①：初回の英文

Semiconductors are the medium between conductors that can conduct electricity all the time and insulators that can't conduct any electricity at all.
Semiconductors are often used like switch from zero to one because it can conduct electricity some time and can't conduct other time.
So they can be used in many circuits to send electrical signals when they receive radio wave that contains information.

評価：65点程度

• 文法ミスや表現の不自然さがありました。
• 意図は伝わるが、より明確な構成・専門用語の使い方が必要です。

添削案①

Semiconductors are materials that fall between conductors, which always conduct electricity, and insulators, which do not conduct electricity at all.
Because semiconductors can conduct electricity under certain conditions but not under others, they are often used as switches — turning "on" or "off" like binary states (0 and 1).
This property makes them useful in many electronic circuits, such as for transmitting electrical signals when receiving radio waves that carry information.

改善点

• 専門用語（binary states, transmit）を明確に使用。
• 文法ミスを修正。
• 「0と1」のような使い方を明確に表現。

原文②：書き直しバージョン

Semiconductors have property that can conduct electricity in some condition and on the contrary they cannot conduct any electricity.
Therefore they can be used as switches to transmit on and off signals.
They can be produced by putting some atoms such as boron and phosphorus into pure silicon or other elements.
Recently, the largest semiconductor company called TSMC has built huge factory in Kumamoto, Japan.

評価：85点

• 表現力が向上し、話の流れもスムーズ。
• ただし、一部の文法・語法・冠詞のミスが残っている。

添削案②（最終バージョン）

Semiconductors have the property of conducting electricity under certain conditions, while under other conditions, they do not conduct electricity at all.
Therefore, they can be used as switches to transmit "on" and "off" signals.
They are produced by adding small amounts of atoms such as boron or phosphorus into pure silicon or other base materials.
Recently, the world's largest semiconductor company, TSMC, built a huge factory in Kumamoto, Japan.

改善点

• "property of ～ing" のような自然な構文へ修正。
• "by putting" → "by adding" のように科学的な表現に変更。
• 冠詞（a/the）や前置詞の適切な使用を徹底。

まとめ

このように、英語で専門的な内容を説明する際には、

• 文法の正確さ
• 専門語の自然な使用
• 文のつながりと論理展開

が重要です。

自分の書いた英文を見直し、少しずつブラッシュアップすることが、英語力を確実に高める近道です。

ぜひあなたも、身近なテーマで英語説明文を練習してみてください。