問題: What kinds of sports are popular now but not popular 50 years ago?

Extreme sports like skateboarding and BMX are really popular now, especially among young people. They weren't around 50 years ago. These sports are exciting and a bit risky, which makes them really appealing. Plus, they're often featured in big competitions like the X Games, which helps increase their popularity.

Extreme sports such as skateboarding, BMX, and parkour have seen a significant rise in popularity over recent decades. These sports, characterized by their adrenaline-pumping nature, were virtually non-existent 50 years ago. Today, they not only attract a large youth demographic but are also prominently featured in major extreme sports events, adding to their appeal and visibility.

1. 過去完成進行式:「在受到顯著的普及」使用過去完成進行式來描述一個自過去開始並持續到現在的持續性動作，為所討論的時間軸增添深度。 2. 被動語態:「在50年前幾乎不存在」使用被動語態來強調50年前這些運動的狀態，而不具體說明是誰認為它們不存在，這增添了正式的語氣。 3. 現在完成進行式:「也被突出地展示」使用現在完成進行式來描述當下的持續性動作，由於過去的行動而具有相關性，有效地將過去和現在聯繫在一起。

E-sports have become incredibly popular recently. They involve competitive video gaming, which wasn't possible 50 years ago because the technology didn't exist. Nowadays, there are big tournaments and even professional e-sports players, which shows how big it has become.

E-sports, or competitive video gaming, has emerged as a major sport, drawing massive audiences worldwide. This phenomenon was unimaginable 50 years ago due to the absence of necessary technology. Today, e-sports encompass organized, professional competitions and have even begun to offer lucrative careers and scholarships, reflecting its establishment as a legitimate and popular sport.

1. 過去完成進行式：「在50年前是無法想像的」使用過去完成進行式來強調電子競技的歷史性不存在，為時間背景增添深度。 2. 現在完成式：「已經成為主要運動」使用現在完成式來描述從過去到現在的最新發展，突顯電子競技的持續相關性和增長。 3. 被動語態：「甚至已經開始提供豐厚的職業和獎學金」使用被動語態來聚焦於主語（職業和獎學金）所接受的行動，強調電子競技產業提供的好處。

MMA, or mixed martial arts, is really popular now, but it wasn't around 50 years ago. It combines different fighting styles, which makes it very interesting to watch. Organizations like UFC have helped it gain a lot of attention and a big following all over the world.

Mixed Martial Arts, commonly known as MMA, has dramatically risen in popularity, particularly with the emergence of organizations like the UFC. This sport, which integrates various combat styles, was nearly non-existent 50 years ago. Today, it captivates a global audience and enjoys extensive media coverage, highlighting its evolution into a widely recognized and followed sport.

1. 現在完成進行式：「在過去急遽地增長」- 這個時態用來表示一個行動從過去開始一直持續到現在，強調綜合格鬥搏擊運動在受歡迎度持續增加。 2. 關係從句：「整合了各種格鬥風格」- 這個從句提供有關綜合格鬥搏擊運動的額外資訊，增強該描述並增添句子的深度。 3. 被動語態：「被全球觀眾所吸引」- 使用被動語態將焦點從執行行動的主語轉移到行動本身，強調綜合格鬥搏擊運動的廣泛影響。