Synthetic plant creates fuel from sunlight 4 subject verb errors

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The text below contains 4 subject-verb errors. Correct them.

Synthetic Plant Creates Fuel from Sunlight

British scientists might of solved one of chemistry’s most difficult issues: the creation of a synthetic leaf.  

Researchers at the Occidental Research Bureau has struggled for three decades to produce a man-made leaf able to absorb CO₂ from the atmosphere and convert it into chemical energy. Yet now it seems that they have at long last achieved their goal.  

“Everyone in the bureau are responsible for this success,” said Professor Giles Smiley, the chief scientist leading the research efforts. The staff’s attitude have been faultless

The four errors and their corrections are:

British scientists might of solved --> British scientists might have solved

Researchers at the Occidental Research Bureau has struggled --> Researchers at the Occidental Research Bureau have struggled

Everyone in the bureau are responsible --> Everyone in the bureau is responsible

The staff’s attitude have been faultless --> The staff’s attitude has been faultless

Explanation:

It is common to see "might of" or "could of" being used in informal texts. However, such phrases are incorrect. Their use happens when people confuse the verb "have" with the preposition "of", because they sound similar when pronounced amidst other words. Thus, the first error is "might of", and its correction is "might have".

For the second error, the problem is that the subject is "researchers", which is plural, but the verb form "has" is singular. To correct it, we must use the plural verb form "have".

For the third and the fourth errors, we have singular subjects ("everyone" and "attitude") and plural verbs ("are" and "have"). To correct them, we can use the singular forms "is" and "has", respectively.