The noun forms for the verb to observe are observer, observance, observation, and the gerund, observing.
A related noun form is observatory.
'Observe' is a verb. In the English language verbs do not take a plural form when the related noun or pronoun is plural.
e.g.
Singular - Plural I observe - We observe
You observe - you observe
He/she/it observes - they observe
Observe/observes is the verb form of observation.
observer
Observable
Only the month of May (a noun) can form a plural, and the plural of a month is formed by adding S (e.g. For the last few Mays, he has visited the village to observe the holiday). For January and February, an -ies form also may be used.
Occurrences is the plural of occurrence: On how many occurrences did you observe Mr. Gray waiting in the lobby?
Bridges is the plural form of bridge.
There is no plural form for the word, countries. This word itself is a plural.
"Beliefs" does not have a plural form, as it is already plural. Beliefs is the plural form of belief.
Only the month of May (a noun) can form a plural, and the plural of a month is formed by adding S (e.g. For the last few Mays, he has visited the village to observe the holiday). For January and February, an -ies form also may be used.
Occurrences is the plural of occurrence: On how many occurrences did you observe Mr. Gray waiting in the lobby?
Bridges is the plural form of bridge.
"Beliefs" does not have a plural form, as it is already plural. Beliefs is the plural form of belief.
There is no plural form for the word, countries. This word itself is a plural.
"Groceries" is the plural form of "grocery."
The plural form of "meter" is "meters."
The plural form for the noun sergeant is sergeants; the plural possessive form is sergeants'.
It has no plural form.
The plural form of rung is rungs.
The plural form of mouth is mouths. The plural form of month is months. The Mounth is a range of hills in Scotland and does not have a plural form.
The plural of "she" is "they", so the plural of "she had" is "they had".