Subject-Verb Agreement In The Present Tenses
In the present tenses, verbs change in form to agree with their subjects.
The cars move to the side of the road as the hot-air balloon moves slowly toward the median strip. The balloonist is calling out greetings while the police are calling to him through their megaphones. He has floated hundreds of miles under this patchwork canopy, and the winds have always floated him to his landing sites.To agree with singular subjects other than I or you, simple present tense verbs take an added -s, and verbs in the present progressive or perfect tenses include a final -s in their auxiliaries. (Review Chapter 11 for these verb forms.)
Remember that the English language uses final -s in two different ways:Subject-verb agreement, then, implies that there's room for only one added -s in any subject-verb combination.
- -s added to a noun means plural.
- -s added to a verb means singular.