I am unsure of whether the verb should be plural or singular in this sentence. I am confused because I am unsure whether it is 'network' or 'glands and tissues' that the verb needs to agree with. The sentence is from a glossary

Endocrine System: A network of glands and tissues that secrete hormones directly into the bloodstream.


Endocrine System: A network of glands and tissues that secretes hormones directly into the bloodstream.

Any advice would be greatly appreciated.
Thank you very much.
This is more a matter of fact than of grammar. It seems to me that a "network" is too abstract an entity to secrete hormones. It is, as a matter of fact, the glands and tissues that make up the network which secrete the hormones. I would use the first one. (that secrete hormones).

either or would work.
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 CalifJim's reply was promoted to an answer.
  • You will not find the subject in a modifying phraseEmotion: mobile phone, a phrase that starts with a preposition, a gerund, or a relative pronoun and that modifies the meaning of the noun or subject under discussion.
    The group of students is going on a field trip.
    Subject: the group
    MP: of students
    Verb: is

    The survey covering seven colleges reveals a growth in enrollment.
    Subject: the survey
    MP: covering seven colleges
    Verb: reveals

    The speaker whom you saw at the lecture is one of the state senators from Minnesota.
    Subject: the speaker
    MP: whom you saw at the lecture
    Verb: is

    This might help.

  • Thank you everybody for your time and knowledge.
    It is much appreciated. I will take your ideas on board.
    Best Wishes,
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