By comparing the frequency of English expressions with that of katakana expressions using the data in Tables 2 and 4, we found that adverbs and adjectives, such as "アップ" (up) and "デ ジタル" (digital), that are often used in Japanese are often expressed using katakana and that prepositions that are not used so often in Japanese are not often expressed using katakana.
we found a trend in which English expressions that have been used often in Japanese are likely to be expressed with katakana and English expressions that have not been used often in Japanese are likely to be expressed using the Roman alphabet.