At a glance
Noun にすら means "even (to / in / for) [noun]". It picks out an extreme case, often in a negative sentence, and sounds formal or written.
[Noun] に + すら
彼は家族にすら本当のことを言わなかった。 He didn't tell the truth even to his family.
How to form it
Start with a phrase that already needs に, then add すら after に:
| Attaches to | Base phrase | With にすら | Register |
|---|---|---|---|
| Noun + に (person you tell, ask, etc.) | 親友に話す | 親友にすら話さない | Formal, written |
| Noun + に (place) | 地図に載っている | 地図にすら載っていない | Formal, written |
| Noun + に (person who can / understands) | 子どもにわかる | 子どもにすらわかる | Formal, written |
すら comes after に: にすら, not すらに.