不好意思我忽略了这个 英语怎讲?

正确答案应该是:I'm sorry to have ignored it. 这才是地道的表达法．

Sorry, I forgot it! / I ignored it.

如果你是要补充前面忘记说的用 by the way 就行了

Excese me/sorry ,I missed it.

Sorry for my ingnorance on it.

Sorry, I forgot it!

It's a shame that I miss it .