Learn Hardcore Hebrew: המערכת במשרד לא עבדה בבוקר, ולכן שום קובץ לא נשלח. - The system at the office did not work in the morning, so no file was sent.

מערכת is a feminine singular noun in Hebrew. Because Hebrew verbs agree with the subject in gender and number, the verb in the first clause is עבדה, the feminine singular past form.

So:

המערכת עבדה = the system worked
if the subject were masculine, you would expect עבד

This kind of agreement is very important in Hebrew, especially in the past tense.

Why doesn’t Hebrew use a separate word for it here?

Hebrew usually does not need an explicit subject pronoun when the subject is already stated.

In English, you might say:

the system ... it didn’t work

But in Hebrew, once you have המערכת, there is no need to add היא unless you want special emphasis or contrast.

So המערכת לא עבדה is the normal way to say it.

What exactly is במשרד, and why is it written as one word?