1 . I find________ hard to concentrate on my studies with some people having small talks around me.(用适当的词填空)

2 . ___________________(据报道) the 20th National Congress of the Communist Party of China was held in Beijing on October 20.   (report) (根据汉语提示完成句子)

3 . Spending too much time online is unhealthy and makes_____________(很难把精力放在生活中的其他事情上。). (根据汉语提示完成句子)

4 . 在过去科学家觉得难以解决地球上生命是如何开始的问题。
In the past, scientists ____________ solve the problem how life began on the earth. ( find)