adj.
VERBS
▪ appear , be , prove , seem
▪
The age barrier appeared ~.
▪ become
ADVERB
▪ almost , nearly , virtually
▪ apparently , seemingly
▪
They were now faced with seemingly ~ technical problems.
Insurmountable is used with these nouns: ↑ barrier , ↑ difficulty , ↑ obstacle , ↑ odds , ↑ problem