I'd just like to emphasise (for those that are still confused by this layout) just how the voices work and interleave with each other.
Following is the bar re-created with MuseScore with each of the voices in a different colour - Blue (primary), Green (Secondary) and Gold (Tertiary). The same colours are duplicated in the guitar tabulature to emphasise how they are transcribed from score to tabulature notation.
You can clearly see in this image how each of the three voices has its own timebase to work from. The primary voice is played on the beat (1-2-3-4). The secondary is played on the half-beat (and-1-and-2-and-three-and-four) offset by the quaver rest at the start (also in green). The tertiary voice is notation more normally seen for multi-voice layouts, and has the more obvious beat 1-3.
While this format is frowned upon by music purists it does make for a cleaner layout. It is though, as you have seen, slightly more cryptic than the more explicit (and correct) notation shown by @WheatWilliams, but once you have got used to looking for this style (and especially noticing that elusive rest at the start of the secondary voice) it becomes just as readable as the more strict layouts.
Personally I don't know which method is better - the strict (though maybe overwhelming to the beginner with all those ties) notation or the loose (which makes it clearer what the length of the notes are if not the timing) notation. Suffice it to say, though, that with the loose notation becoming more and more common it's important to get used to reading both of them and translating, in your head, between the two.