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It has been a long day is the most popular phrase on the web.

It have been a long day 1129,000 results on the web	It has been a long day 1366,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It's been a long day, Steve. It's been a long day. It's been a long day. Actually, Your Honor, it's been a long day for Avery. You know, it's been a long day. It has been a long day for Christoffer with all this attention. It's been a long day for both of us. It's been a long day already.	It has been a long day. I'll have my guards walk you safely home. It's been a long day, Steve. It has been a long 10 days, and I am parched. Mike... It has been a really... long day. It has been a long, stressful day. It has been a long day for Christoffer with all this attention. Yes, I said that, and it might be true, but this has been a long day and I've had a long time to look at this world I've created. It has been a long day, Leo.

It have been a long day

1129,000 results on the web

It has been a long day

1366,000 results on the web

More popular!

It has been a long day. I'll have my guards walk you safely home.
It's been a long day, Steve.
It has been a long 10 days, and I am parched.
Mike... It has been a really... long day.
It has been a long, stressful day.
It has been a long day for Christoffer with all this attention.
Yes, I said that, and it might be true, but this has been a long day and I've had a long time to look at this world I've created.
It has been a long day, Leo.