The workers at the mill (is/are) planning to strike.

The correct answer is "are". In English grammar, we need to take into account subject-verb agreement.

In this case, the noun "workers" is in the plural so the correct form of the verb "to be" should also be in the plural form (are).

Subject-verb agreement is achieved when the form of the verb "agrees" with the subject. (plural-plural; singular-singular)

The correct sentence reads as follows:

"The workers at the mill are planning to strike."

wonder full my friend keep going

beowulf sets out on his journey for daneland. -- 1

hrothgar welcomes beowulf. -- 2

beowulf waits for grendel to attack heorot. -- 3

beowulf succeeds in defeating grendel by tearing off his arm. -- 4

beowulf fights with grendel’s mother. -- 5

beowulf sets out for his fight with the dragon. -- 6

beowulf sets out for his geatish homeland. -- 7