Learn Russian: Что бы ни случилось, я смогу защитить обоих детей. - Whatever happened, I will be able to protect both children.

In Russian, the construction of an interrogative pronoun + бы ни + past tense expresses a universal or hypothetical concession, like "whatever happens" or "no matter what happens". The particle бы triggers the past tense form to create this hypothetical meaning, even when the actual context is about the future or present.

Why do we use the particle ни instead of не before the verb?

In this construction, ни does not negate the verb. Together with the question word (что) and бы, the particle ни translates to "-ever" or "no matter what". If you used не instead, it would be a standard negation, changing the meaning to "whatever would not happen".

Why is the word for "both" translated as обоих rather than оба?

The numeral оба (both) declines based on gender, case, and animacy. Here, it is in the accusative case because it is the direct object of защитить (to protect). Since детей (children) is an animate noun, the accusative form matches the genitive form, making it обоих (the form used for masculine or mixed-gender groups). If the noun were inanimate, it would remain оба.

Why are смогу and защитить in the perfective aspect here?