You can cascade a set of context prefixes, optionally separated by commas, onto one subject expression, effectively applying all the contexts (in order) to the subject expression. For example:
animate on, at time (t+1), with undo off, coordsys local
(
...
)
All the context forms are true expressions, yielding the value of their subject expression, so:
pos0 = at time 35 $box01.position
pos1 = at time 75 $box01.position
assigns the box01 position at time's 35 and 75 to variables pos0 and pos1. This is particularly useful with the at time context, as you can very easily do across-time computations. The operand to an at time context can be any valid time value (numbers are taken as frames for convenience), including sub-frame times down to the tick level. The animation system in 3ds max will interpolate animated parameters at these fine levels so you can easily do sub-frame simulation computations.