There is

it's really a good idea.\u4e3a\u4ec0\u4e48\u4e0d\u662freal\uff0creally\u4e0d\u662f\u526f\u8bcd\u5417

real\u662f\u5f62\u5bb9\u8bcd\uff0c\u5f62\u5bb9\u8bcd\u7684\u8bed\u6cd5\u529f\u80fd\u662f\u4f5c\u5b9a\u8bed\u6216\u8868\u8bed\u3002really\u662f\u526f\u8bcd\uff0c\u526f\u8bcd\u7684\u8bed\u6cd5\u529f\u80fd\u662f\u4f5c\u72b6\u8bed\u3002\u6b64\u53e5\u4e2dit\u662f\u4e3b\u8bed\uff0cis\u662f\u7cfb\u52a8\u8bcd\uff0ca good idea\u662f\u8868\u8bed\uff08\u5176\u4e2dgood\u662fidea\u7684\u5b9a\u8bed\uff09\uff0creally\u4f5c\u72b6\u8bed\u3002

\u4e00\u3001\u8bcd\u4e49\u5e7f\u6cdb\u6027\u4e0d\u4e00\u6837
real
\u82f1 [ˈri:əl] \u7f8e [ˈriəl, ril]
1\u3001adj.\u771f\u7684\uff1b\u771f\u5b9e\u7684\uff0c\u73b0\u5b9e\u7684\uff1b\u4e8b\u5b9e\u4e0a\u7684\uff1b\u771f\u8bda\u7684
2\u3001adv.\u771f\u6b63\uff0c\u5b9e\u5728\uff1b\u786e\u5b9e\u5730
3\u3001n.\u5b9e\u5728\uff0c\u73b0\u5b9e\uff1b\u5b9e\u6570
really
\u82f1 [ˈri:əli] \u7f8e [ˈriəˌli, ˈrili]
adv.\u5b9e\u9645\u4e0a\uff1b\u771f\uff0c\u771f\u6b63\uff1b\u5b9e\u5728\uff0c\u679c\u771f\uff1b\u4e8b\u5b9e\u4e0a
\u4e8c\u3001\u8bcd\u6c47\u642d\u914d\u4e0d\u4e00\u6837
real
1\u3001real fears\u786e\u5b9e\u6050\u60e7
2\u3001real illnesses\u7684\u786e\u75c5\u4e86
3\u3001real knowledge\u771f\u77e5

really
1\u3001really cold\u975e\u5e38\u51b7
2\u3001really fast\u975e\u5e38\u5feb
3\u3001really long\u975e\u5e38\u957f
\u4e09\u3001\u8bcd\u8bed\u7528\u6cd5\u4e0d\u4e00\u6837
real\u53ef\u7528\u4e8e\u6709\u5f62\u7684\u4eba\u548c\u7269\uff0c\u4e5f\u53ef\u7528\u4e8e\u65e0\u5f62\u7684\u4eba\u548c\u7269\uff0c\u53ef\u6307\u5b9e\u9645\u5b58\u5728\u7684\uff0c\u662f\u81ea\u7136\u751f\u6210\u7684; \u4e5f\u53ef\u8868\u793a\u201c\u540d\u201d\u4e0e\u201c\u5b9e\u201d\u76f8\u7b26\uff1b\u5728\u8868\u793a\u827a\u672f\u5851\u9020\u7684\u4e0e\u5b9e\u9645\u5b58\u5728\u7684\u5f88\u76f8\u50cf\u65f6\u53ef\u8bd1\u4f5c\u201c\u903c\u771f\u7684\u201d\uff1b\u7528\u4e8e\u996e\u6599\u6216\u98df\u54c1\u65f6\uff0c\u662f\u6307\u4ee5\u6700\u53ef\u9760\u7684\u4f20\u7edf\u65b9\u5f0f\u5236\u4f5c\u7684\uff0c\u7eaf\u6b63\u7684\u3001\u5730\u9053\u7684\u3002
really\u7684\u57fa\u672c\u610f\u601d\u662f\u201c\u771f\u6b63\u5730\uff0c\u786e\u5b9e\u5730\u201d\uff0c\u901a\u5e38\u7528\u4e8e\u9884\u6599\u5bf9\u65b9\u4f1a\u6709\u4e0d\u540c\u610f\u89c1\u7684\u573a\u5408\uff0c\u56e0\u800c\u542b\u6709\u201c\u786e\u5b9e\u5982\u6b64\uff0c\u4e0d\u9a97\u4f60\u201d\u7684\u610f\u601d\uff0c\u6709\u65f6\u4e5f\u7528\u4e8e\u8868\u793a\u60ca\u5947\u6216\u542b\u84c4\u7684\u6000\u7591\u3002really\u4e5f\u53ef\u4f5c\u201c\u5f88\uff0c\u5341\u5206\u201d\u89e3\u3002

应该填really。
句子你可以这么分解，There is really a good football team.=Really, there is a good football team.=There is a good football team, really.
这里的really是副词做状语的。

修饰there is 中的动词is

扩展阅读：there is an old saying ... there is to be ... those are my parents ... there is 句型 ... there be doing ... the books ... there is no game ... there is a desk ... there is an elephant ...