1. Both fans are running2.Both fan is running 3.Both diesel generators were serviced 4.Both diesel generator was serviced5.Both diesel generators had been serviced. / Has been servicedWhich one is correct, and why?
None of them are correct. There should be a period or some form of punctuation at the end of a sentence.
There are two correct sentences in this group: 1. Both fans are running. 2. Both diesel generators were serviced. These sentences have the correct tense and verb format.
These three are correct - 1. Both fans are running (are, because both fans is plural) 3.Both diesel generators were serviced (were, because generators is plural) 5.Both diesel generators had been serviced (you can also say have been serviced, if they've been serviced recently. EDIT.@Diane: None of them is singular; therefore is correct.and the question doesn't concern punctuation.
Both fans are running is correct. You are talking about more than one item, therefore the plural are is correct. Both diesel generators were serviced is correct, for the same reason. The first part of the last sentence, both diesel generators had been serviced is also correct if you are talking about the past historic tense.
