why引導(dǎo)定語從句,修飾reason,這里的why=for which.
The reason for which i come here is very clear.
come here是個完整詞組,不缺賓語.why在從句中做狀語.
最后,這個句子可以分解為:
I come here for this reason.
This reaon is very clear.come here 為不及物動詞詞組嗎？可以這樣理解。come here是個動詞+副詞的短語，后面不需要賓語。及物動詞或介詞的后面才需要跟賓語。