Grammar - Beginner - Part 3
kanarazushimo かならず 必ずしも
Adverb (used with a negative) meaning: (not) always, (not) necessarily, (not) all
It can be shortened to kanarazu 必ず, or replaced by itsumo いつも.

1. Used with negative

お金は必ずしも必要ではない。
O-kane wa kanarazushimo hitsuyou dewa nai.
Money is not always necessary.

2. Used with dictionary form of verb/adjective + to wa kagiranai (not necessarily, not always)

それが必ずしもうまく行くとは限らない。
Sore ga kanarazushimo umaku iku to wa kagiranai.
It will not necessarily go well.

先生が必ずしも正しいとは限りません。
Sensei ga kanarazushimo tadashii to wa kagirimasen.
The teacher is not always right.