因为前面有“be”,所以后面的help要加上ing
You should all be helping each other to improve.和
You should all help each other to improve.语法上都对,前面一句的语气更重一些.You should all be helping each other to improve.是现在进行时吗？You should all be helping each other to improve和You should all help each other to improve.这两句意思有区别吗？谢谢可以理解为现在进行时，两句的意思，前面说了，用be helping更加强调一些。