Hi folks In new media, I can hear a lot of people saying "I argue that .." I looked it up and found out that it means "give reason for your statement?" For example, - Mr. Trump appeared to side with pro-Brexit critics who argue that by keeping many of the European Union’s economic rules, it would inevitably reduce the scope for a separate trade deal with the United States. - Supporters of Brexit argue that one of the key advantages of quitting the European Union would be that it would leave Britain free to strike trade deals around the world. To me, it sounds like 'argue that' is used to give your opinion on something. Therefore, I'm guessing 'I argue that' can be interchanged with ''I would say~" or "I believe". But it's just my feeling and guess. I would like to know if they are pretty much the same expression and can be used interchangeably. And if there's any difference in terms of nuance and meaning. Please explain them to me, I would appreciate it.