metastases
The word metastasis is singular, metastases is plural.
Metastases
Metastases is the plural formation of the word mestasis.
Metastasis
Depends on the form. If cancer has spread, it is said to have metastasized. The spreading itself is called metastasis. "Lung carcinoma with metastasis to the liver."
There is no plural form. Do and Do not are verbs
The plural form of him, her, or it is them. (objective pronouns)
Bridges is the plural form of bridge.
The plural form of "was" is "were."
The plural form of "I" is "we."
The plural form of "is" is "are."
"Groceries" is the plural form of "grocery."