IPA発音、定義、例文、インタラクティブクイズ付きの重要な単語。
種類タグ、二言語の定義、使い方の説明、例文を含むフレーズ。
To maintain a leading position over rivals in a market or field.
A camera lens designed for taking photographs of still or moving subjects at long distances.
The frequency with which the image on a computer monitor or display screen is updated, measured in Hertz (Hz).