Divide line into 3 segments of infinite length

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Is it possible to divide line (I mean line of infinite length, $[-\infty, +\infty]$) into a three segments of infinite length? My common sense says it's not possible, because every 2 points define segment of finite length, but am I right?

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Your intuition is correct. It is not possible to partition the real line into three non-overlapping infinite intervals.

Suppose we have three such intervals.

The intervals do not overlap, so only one can extend to $-\infty$. Thus, two of the intervals must have finite left endpoints. Similarly, only one can extend to $\infty$, so two of the intervals must have finite right endpoints.

By the pigeonhole principle, at least one interval must have both endpoints finite. That makes it a finite interval, contradicting our assumption.

Therefore, no such intervals can exist.