Breakdown of Мир вокруг нас изменяется по мере того, как память слабеет.
мы
we
мир
world
память
the memory
вокруг
around
Questions & Answers about Мир вокруг нас изменяется по мере того, как память слабеет.
How exactly does the phrase по мере того, как work here, and why is the comma placed before как?
По мере literally means "by the measure". The entire phrase по мере того, как acts as a compound conjunction meaning "in proportion to how" or simply "as" (when describing simultaneous, gradual changes). In Russian, it is standard punctuation to place the comma right before the final linking word of a compound conjunction (in this case, как), rather than before the whole phrase.
Both verbs in this sentence (изменяется and слабеет) are imperfective. Is that required when using по мере того, как?
Almost always, yes. Because по мере того, как specifically describes a gradual, ongoing progression or correlation between two processes, it naturally requires imperfective verbs. Using a perfective verb would imply a sudden, completed result, which contradicts the meaning of "in proportion as".
Why does the verb изменяется (changes) have the reflexive -ся ending in this sentence?
In English, "change" works for both doing it to something else ("I change the rules") and happening to a subject ("The world changes"). Russian strictly separates these. Because the world is changing by itself—not changing some other object—you must use the intransitive, reflexive form изменяться. If you used изменяет, a Russian speaker would wait to hear what the world is changing.
The verb слабеет means "weakens". Is there a reliable pattern for forming verbs like this from adjectives?