overlook,neglect,ignore都有忽略、忽视的意思.
（1）ignore v.忽视,不理睬,指有意识地拒绝.
She saw him coming but she ignored him.她看见他走过来,但是装作没看见.
（2）neglect v.忽视,忽略,疏忽,指无意识地忽视或忘记.
He neglected to make repairs in his house.他忘记了修理房子.
（3）overlook v.忽略,疏漏,指有意识地遗漏,也可以指无意识地忽略.
The mother overlooked her little boy's bad behavior.那位母亲忽视了她的小儿子的不良行为.