"In het bos bleven de kruizen achter".
Plural of kruis is kruisen. (kruizen looks like a verb that does not exist)

I take it the -z- is pronounced like an /s/, or at least has begun to do so recently. Quoting a Frenchman peeving about English "grammar" about a Dutch orthographic peeve is a bit much even for my rootishness.

Ceci n'est pas un seing.