Ducking Fx under vocals?

Hi all,
Qu-SB newbie here.

Digging around it looks like I should be able to duck say the Delay/Verb FX under say the lead singer’s vocals so that a nice FX tail comes in at the end of a phrase, but I can’t seem to work out how to do it…

Any suggestions welcome thanks

PS. I’d also like to retain overall control of the Fx levels, so I can vary how much ducking / non-ducking occurs on the fly.

Thanks in advance!

FX return channels lack dynamic tools, so you’d need to feed your FX into a group, and process it there.

Ok, thanks.