Daniel Ehrenberg wrote:
Imho, better trust us to have imagination and to find ways to turn around things. In France, I would say the toughest is not the law, the toughest are (is ?) the barriers people build themselves thinking of the law. Anthere
I think it's is. The verb should agree with the subject, and the subject is singular. --LittleDan
"Are" is correct. The implicit subject is "barriers" -- plural
Ec