The expression NOW THAT I THINK ABOUT IT is used to express your view or feeling about sth after having the chance to better analyze sth.
Now that I think about it, I’m not sure it’s a good idea to quit your job right now.
I know I let you go, but now that I think about it, maybe you shouldn’t.
Yes, I did agree, I remember, but now that I think about it, I think it was a mistake.
I thought I was right, but now that I think about it, I’m not so sure anymore.
I know you don’t have to tell me everything, but now that I think about it, I think you should have told me that.
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