The possessive form for the noun soil is soil's.
volcanoes'
The plural form of the noun volcano is volcanoes.The plural possessive form is volcanoes'.Example: The government monitors many volcanoes' activitywith a network of instruments.
The plural form of the noun volcano is volcanoes.The plural possessive noun is volcanoes'.Example: Hawaii has two active volcanoes, Kilauea and Mauna Loa. The volcanoes' activity is monitored by the US Geological Survey.
The volcanos' rocks
The plural is relatives. The plural possessive is relatives'.
The plural is lads. The plural possessive is lads'.
The plural form is Mexicans. The plural possessive is Mexicans'.
The plural possessive of stepsister is stepsisters'.
The plural form is inches. The plural possessive is inches'.
The plural form is suffixes. The plural possessive is suffixes'.
The plural form is echoes. The plural possessive is echoes'.
Coaster's is singular possessive. The plural is coasters, the plural possessive is coasters'.
The plural possessive is pals'.
Studies' is the plural possessive of study.
The plural possessive form of "weeks" is "weeks'."
The plural possessive of bandit is bandits'.