Explorers.
The plural of quarry is quarries.
The plural of Egyptian is Egyptians.
The plural of Inca is Incas. "Incans" is not the correct plural form.
The plural of artifact is artifacts.
The spelling tombstones is the plural form; the singular form is tombstone.
The explorer's sock (singular possessive) The explorers' socks (plural possessive)
The explorer's sock (singular possessive) The explorers' socks (plural possessive)
Explorers
The possessive singular noun is explorer's. The possessive plural noun is explorers'.
This is not difficult if you think about the meaning of what you are writing. The word 'ten' indicates a plural noun ('ten' is more than 'one'). Therefore the word following it must be plural: the equipment belongs to ten explorers, not to ten explorer. Therefore the apostrophe must come after, not before, the 's' of 'explorers': 'The ten explorers' equipment had been carefully selected and packed.'
An explorer.
The plural of "she" is "they", so the plural of "she had" is "they had".
The plural of 'this' is 'these' and the plural of 'that' is 'those'.
Isthmi is plural. There are actually two plural forms. I will list them from singular to plural. Isthmus - Singular Isthmi - Plural Isthmuses - Plural
The plural of rose is roses. The plural possessive is roses'.
he was a french explorer
applied is does not have a plural but is apply it does have a plural.