combine expressions on FX-9860Gii

On the TI-84, it is possible to combine several expressions; e.g. -2 --> A : 3 --> B : A + B²

store -2 into variable A ; store 3 into variable B ; then evaluate

Can this be done on the FX-9860Gii ?

You mean combine with ":"? I think so, it is possible on fx-5800P which has a more simple version of Casio BASIC. But is connecting them with ":" more combined than connecting them with a newline character?

Probably a bit late, but you can absolutely do this with one caveat; you must be in line mode  to do so (ShiftMENU ie 'SET UP'), toggle Input/Output between linear and Math).  This then allows you to access the colon to separate expressions via 'PRGM' (ShiftVARS, F6 and you should see it on the right).

Luckily the fx-9860GII seems to not only keep separate memories for math and line mode (so a unique equation history is saved for both modes), but also allow shared variable storage and the copying of equations between modes.  I found it pretty nice that it also handles all the formatting so any equation you make in line mode and then copy to math mode will automatically get converted to Natural textbook style and vice versa.

In addition Line mode allows you to store an additional 20 formula's (on top of the table/graph ones); switch to line mode, recall the formula, copy it and switch back to math mode then paste it.