常常这个疼痛没有明显的原因
he goes to concerts quite often
he often goes to concerts.
there is /there are /there was /there were
通常，没有明显的原因（导致）这个疼痛。
Quite often there is no obvious cause of the pain.
generally
A cause B A导致B
cause 原因(noun)
reason
the reason for 。。。。
the cause of ......
the cause of the fire/emergency 不好的结果
cause 表示一种直接的原因
reason 中性，推过推理得到的原因，不是直接的原因
Quite often there is no obvious cause of the pain.
excuse 借口
Quite+often there is no obvious cause+of the pain.
obvious
b 轻读
v 浊辅音
上门牙轻轻的咬住你们下嘴唇，就发这个音，然后再发的时候，你们会感觉到你的嘴唇跟牙齿跟你的声带都是正振动等，
pain （n的发音 要发出来）
pay
there is
