Grammar · Free lesson
One of my friends is: a plural group, one person
Two number decisions appear in the same sentence. You are choosing one person from a group, so the noun and main verb do different jobs.
Professor Scott MendozaThe short answer
Say One of my friends is here. Friends names the group; one selects a single member. Keep the noun plural after one of, and use a singular main verb such as is, has or works.
The group is plural. The selected member is one.
In One of these keys opens the door, these keys identifies several keys. The sentence says that one key opens the door, so the verb is opens. Changing it to All of these keys open the door changes both the number and the claim.
Compare the examples
One of my friends is here.
One of these keys opens the door.
All of these keys open the door.
One of my friend is missing the plural group noun. One of my friends are has the wrong main verb for one.
Build the meaning step by step
Name the group
these keys
Select one member
one of these keys
Match the main verb to one
One of these keys opens the door.
Try it now
Keep the group and the chosen member separate.
Read all answers and explanations
Complete: One of my ___ is a nurse.
cousinsCousins names the group of people. One selects one cousin, so is stays singular. Cousin's with an apostrophe is not the plural form.
Only one bus in this group stops here. Complete: One of these buses ___ here.
stopsOne is the subject head, so stops fits this simple present statement. Buses remains plural inside the group phrase.
Which sentence correctly says that one of several windows is open?
One of the windows is open.Windows is the plural group; is matches one selected window.
Put it into practice
Repair both number choices
Keep one selected bag from several bags. Correct the noun and main verb without changing that meaning.
One of these bag have a broken handle.
See a model answer
One of these bags has a broken handle.
The edit preserves one damaged bag. All of these bags have a broken handle would be grammatical, but it would make a different claim.
A little more clarity
Common questions
A few useful details before you move on.
Why is the noun plural if I mean one?
The plural noun names the group you choose from. One names the number of members you selected.
One of our neighbors has a dog.
What changes with two of?
The group noun stays plural, but the subject now selects two, so the main verb is plural too.
Two of our neighbors have dogs.
Take it into your day
Plural noun after one of; singular main verb for the selected one.
Your next step · Available on Udemy
Connect grammar choices into clear sentences.
You have connected a group noun to a one-person statement. The available English Grammar and English Speaking Master Course develops broader grammar and sentence-building foundations for communicating complete ideas.
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