Poll: The battery of medical tests they did ____ very stressful.
- Votes: 180
- Comments: 2
- Added: January 2015
- Polls: 1,167
- Votes: 687,473
- Comments: 4,844
The verb is singular because "battery" is singular. If you said the fifty medical tests they did... then it would be "were" due to fifty being plural. English, what a pain sometimes!
According to subject verb agreement rule that says when the subject is singular the verb must be singular there since battery is singular subject it takes singular verb ( was)