I often play football with my friends 为什么选wⅰth？

I often play football 意思是: 我经常踢足球。with介词，意思是:和…一起。with my friends 和我的朋友们一起，它是一个介词短语，可以作状语，修饰动词play。当然，这句话还可以说成:My friends and I often play football.

I often play football with my friends.
play sth with sb（和谁一起玩......)
这是英语习惯用法，就像中文的一些习惯用法一样，比如：接二连三，你不会问为什么是二，三一样

with=和....做.... 用在人与人之间共同做某件事
play football with .....=和某人踢球

I often play football with my friends .
意思是：
我常常与朋友一起踢足球。
with 是介词，表示：与...

with 和……一起

I often play football with my friends.
我经常和我的朋友们一起踢足球。

扩展阅读：he often watch tv ... is the river through that ... a swarm of ... phoenix contact ... a band of musicians ... john is in a play ... i often do my homework ... is it often rainy ... the classroom was silent ...