Question

He and I ____ playing yesterday. (was/ were)​

Answer 1

The given blank is filled with were as such: He and I were playing yesterday.

Why did we use were here?

• Were is used because the sentence has plural subjects.

• If the subjects were singular then was would have been used.
• Also, the sentence is in the past continuous tense.
• Use of was and were indicates the sentence being in past tense.
• Keeping the subject in mind one can easily determine the use of was and were.