was it interesting to hear students'什么on the difficult math

Was it very difficult to buy it on the The math problem was very difficult that few students could I found that it was difficult to do the math probiem.I found 1.I found that it was difficult to do the math problem. It was very difficult for me to work out the math problem.同义 I found that it was difficult to do the math problem.（改为简单句） i found that it was difficult to do the math problem改简单句 It was interesting to hear what the class think about action Many students find it's difficult to focus on studies in the The test was very difficult,so(f )students passed it The exam was so difficult that ______ students paased it. It's difficult to see and hear at the back.