(2012·陕西高考)If he takes on this work, he will have no choice but ________ an even greater challenge.

After he retired from office, Tim ________ painting for a while, but soon lost interest.

The thing that matters is not whether you fail or not, _______whether you try or not.

It was such a difficult examination that a lot of students were unable to finish it on time.—That’s the case. It’s hard to accept the fact that over 90% of my classmates ________.

（天津市河东区201 4年高三二模考试）14. I_______ to go for a walk, but someone called and I couldn’t get away.