An isthmus is a narrow piece of land connecting two larger areas across an expanse of water by which they are otherwise separated.
Can you guess this isthmuses (or isthmi) given the two landmasses they connect or the two bodies of water they divide?
And isthmus could divide a lake from a sea or two lakes from eachother
In some hints you are given two landmasses, in other you are given two bodies of water. Sometimes you are simply given "mainland" too
No need to enter "isthmus of" every time, every answer has a type-in without "isthmus"