It is far more difficult to convert cellulose to ethanol than it is to convert starch.
The Iranians had agreed in principle to a deal last year that would have allowed the fuel to be converted overseas and then returned in a form that would be difficult to convert for weapons use, but they later renounced the agreement.
"It's difficult to convert into some common denominator".
Methane and ethane remain difficult to convert by this route.
But the victory won at Cortenuova proved difficult to convert into permanent gains.
Why is it very difficult to convert certain TI-83 programs to run on the TI-83+?
The uranium shipped out would be returned in a form usable for Iran's research reactor but very difficult to convert to weapons production.
"It's nice that he's focussing on God's love, but I think it's going to be difficult to convert the hipsters," one man said.
Captives had been taken far from home, many of them to Syria, and their confused descriptions were difficult to convert into precise coördinates.
It was extremely difficult to convert an intensely acrimonious environment into one in which a culture of collaboration has at least begun to take hold.
