分类：教育/科学-学习帮助
问题：请教一些在作业中的疑问！！①risk风险是名词吧，他有复数形式吗 
①ri风险是名词吧，他有复数形式吗？②是an  effect  还是  a  effect?③steal是偷的意思吧，那他的过去式和过去分词是什么呢？④develop的进行式用双写p吗？⑤选择题：（）the  meeting  himself  gave  them  a  great deal  of  encouragement.A.The  president  will  attendB.The  president  to  attend C.The  president  attended D.T①ri风险是名词吧，他有复数形式吗？②是an  effect  还是  a  effect?③steal是偷的意思吧，那他的过去式和过去分词是什么呢？④develop的进行式用双写p吗？⑤选择题：（）the  meeting  himself  gave  them  a  great deal  of  encouragement.A.The  president  will  attendB.The  president  to  attend C.The  president  attended D.The  president's  attending老师讲的是选D.我不太明白啊，讲一下吧，O(∩_∩)O谢谢
回答：①ri既可作名词，也可作动词。作名词时，即可是可数(a situation that could be dangerous or have a bad result译作“危险的形势或有不良影响的形势”），也可是不可数（the possibility of sth bad happening at some time in the future译作“危险；风险”) ②是an effect，如 have an effect on sb/ have a good effect on sb.（a/an选用，看后面单词的首字母读音：原因因素前用an,辅音因素前用a.如：a university/an umbrella）。③steal是“偷；蹑手蹑脚的行动”的意思，他的过去式stole 过去分词是stolen。④develop的形式变化有：develops、developed、developed、developing。 ⑤选择题： （The president's attending ）the meeting himself gave them a great deal of encouragement. 句子结构分析后，你会发现少了主语，也就是说所签部分用作该句子的主语。D项实质是“动名词的复合结构”，功能上相当于名词或代词，因此可用作主语。例如：Would you mind my opening the door?His being late for class was because of his sleeping too much.