Be helpful be halpful_____be useful_____后面应该添什么介词?

作文Be helpful to others Be helpful to others急! be helpful in be helpful to be helpful for 三者区别即怎么用 a summer bus pass will be helpful be helpful to do为什么不对 有没有be helpful to sb i like to be a helpful be helpful in doing 怎么造句 be a great help还是 be a great helpful Be helpful be halpful_____be useful_____后面应该添什么介词? 对某人有用是be helpful to sb.还是be helpful for sb? be helpful to还是for好像是be helpful to那有be help 怎么好多人说是be helpful to 还有 把问题回答全 ok？ 一个简单的英语翻译短语 try to be more helpful, We should be helpful and _(friend) to others.急``` we should be friendly and helpful to_____(other) you were only trying to be helpful?请翻译 try to be as helpful as you can翻译翻译 1.be useful to_______ 2.be helpful to______3.be important to______4.be necessary to______填doing或do