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they have been observed is the most popular phrase on the web.

they have observed 111,500,000 results on the web	they have been observed 130,600,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	Please note: Species are considered as no longer present in the site e.g. if they have not been observed in the site for a long time. and to determine whether they have been fully and properly observed. The reason why they have not been observed, is that the abuses are carried out by armed groups, especially the political security branch of the security forces, which is responsible only to the President. I have been observed by Americans before. They have been observed wearing hoods and directing offensive operations against Government forces in Mogadishu and neighbouring regions. Should these rules apply, the Commission will investigate whether they have been observed in the choice of advisor for the share transfer transaction mentioned by the Honourable Member. If so, which are they, and how have they been observed? Should these rules apply, the Commission will investigate whether they have been observed in the choice of advisor for the share transfer transaction mentioned by the Honourable Member.

they have observed

111,500,000 results on the web

they have been observed

130,600,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

Please note: Species are considered as no longer present in the site e.g. if they have not been observed in the site for a long time.
and to determine whether they have been fully and properly observed.
The reason why they have not been observed, is that the abuses are carried out by armed groups, especially the political security branch of the security forces, which is responsible only to the President.
I have been observed by Americans before.
They have been observed wearing hoods and directing offensive operations against Government forces in Mogadishu and neighbouring regions.
Should these rules apply, the Commission will investigate whether they have been observed in the choice of advisor for the share transfer transaction mentioned by the Honourable Member.
If so, which are they, and how have they been observed?
Should these rules apply, the Commission will investigate whether they have been observed in the choice of advisor for the share transfer transaction mentioned by the Honourable Member.