How to combine dynamic and static info in a Tooltip

[FranklinAlexander]

I am trying to create a Tooltip that combines static text with dynamic (an attribute), but not finding a way to do it. This is for a label that contains both static and dynamic content and I want the hover text to include the entire label and not have to make a choice between the two. You can see from the image below, when a selection is made in the List widget, the selected county name appears in the label:

I've tried to use an Expression for the Tooltip, but when I try to combine the static text and an attribute in the Expression box I get an invalid expression message. 

Seems weird that you can't do this, is there a trick to this that I am missing?

[JeffreyThompson2 · Accepted solution]

I believe the trick here is "Fish present in " + {County} + " county"

[FranklinAlexander]

Yep, just got it!! Thanks.