Answer:
The children are playing hockey on the frozen pond.
Step-by-step explanation:
Linking verbs are the verbs which shows a relationship between the sentence complement and the subject. The linking verbs helps in elaborating, describing or identifying the subject. At last, it helps in establishing existing condition or relationship of the subject. In the above sentence, the linking verb is 'are'. Herein, the linking verb 'are' identifies the current state of children on the frozen pond.