はもちろんNot only but also, Let alone, Not to mention, Of course

はもちろん, or occasionally は勿論(もちろん), is a phrase in Japanese that presents (A) as being something obvious, while (B) should still be considered/mentioned. In this expression, the adverbial particle は presents (A) as being a stand-alone topic, before the adverb もちろん 'naturally' emphasizes that (A) is what it is. After this, the (B) part of the sentence will describe some other factor that is worth mentioning.

はもちろん will be used directly after noun (A), before the sentence will go on to discuss noun (B). This construction can be translated as 'not only (A), but (B)', 'not to mention (A), (B)', and other similar English expressions.

In many cases, despite (A) being the obvious factor, (B) is being highlighted as sharing similar qualities to (A). This means that in はもちろん sentences, も will almost always be seen after (B).

Caution

While quite similar in meaning to だけでなく, はもちろん is quite a bit more formal. Due to this, it may sound quite stiff in friendly conversation, unless particularly emphasizing something.