Although she didn’t know the best way of getting to places, she insisted that she ____________ the trip properly.

(2013·陕西师大附中模拟)If we had taken such effective measures much earlier, the river ________ so seriously now.

Don't handle the vase as if it ______ made of steel.

There have been demands for the prime minister that he ______ office since the incident happened.

--The mistake_____, I had been more careful.---But you weren’t at that time.