。
'Needless to say' is most often introduced as an idiomatic infinitive expression.
Literal
needless to say [topic-は] infinitive [genitive-の] idiomatic-expression [as-として] introduced-being [subject-が] many [copula-です].
A sentence about English grammar study, itself in Japanese. 不定詞 (ふていし, 'infinitive') and 慣用表現 (かんようひょうげん, 'idiomatic expression') are grammar terminology. 紹介されることが多い ('is often introduced') uses the passive + ことが多い ('it is often the case that'). The English phrase 'needless to say' appears in Latin script, as is common in Japanese English-study materials. A metalinguistic sentence — Japanese talking about English.