Yesterday some people were practicing musical numbers.

were practicing--is that the correct helping verb for the sentence

Yes, it is correct.

Sra

"were" is the helping verb

"practicing" is the verb itself

"were practicing is the whole verb

To determine if "were practicing" is the correct helping verb for the sentence, you need to consider the tense and subject-verb agreement. In this case, "were practicing" is the past progressive tense of the verb "to practice" and it matches the subject "some people."

The past progressive tense is formed by using the past tense of the helping verb "to be" (in this case, "were") followed by the present participle of the main verb ("practicing"). It indicates an ongoing action that was happening in the past.

So, in the given sentence, "were practicing" correctly indicates that the action of practicing musical numbers was happening in the past.