По крайней мере один докладчик будет говорить о здоровье, сне и витаминах.

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Breakdown of По крайней мере один докладчик будет говорить о здоровье, сне и витаминах.

• о: about
• один: one
• здоровье: the health

Questions & Answers about По крайней мере один докладчик будет говорить о здоровье, сне и витаминах.

What exactly does по крайней мере mean, and is it the same as English at least?

По крайней мере is the standard way to say at least in Russian in the sense of “no fewer than / no less than that” or “in any case”.

In this sentence:

По крайней мере один докладчик...
At least one speaker...

it sets a minimum number (one speaker).

A few notes:

• Literally, по крайней мере is something like “by the extreme measure / by the last resort”, but Russians don’t feel that literal meaning anymore; they just feel it as “at least”.
• It can also be used in a slightly different sense, closer to “anyway / in any case / at the very least”:
  
  • Я опоздал, но, по крайней мере, пришёл. – I was late, but at least I came.

In your sentence, it is the numeric “at least (one)”, not the “at least (that’s something)” emotional use, though both overlap a bit in feeling.

Why is it один докладчик and not something like одного докладчика or одним докладчиком?