չէին

In a sentence

• Նրանք չէին գնացել դպրոց, որովհետև էր ծանր անձրև։

  They hadn't gone to school because it was heavy rain.

  In this sentence, "չէին" is used as the past continuous auxiliary verb for forming the negative past continuous tense with the verb "գնացել" (had gone).

• Ես չէի հասկացել, որ բուսական ապուրից սիրում եմ։

  I hadn't realized that I like vegetable soup.

  Here, "չէի" is the singular first-person auxiliary verb in the past perfect tense, used for forming the negative of the predicate "հասկացել" (realized).

• Մենք չէինք լսել նոր երգը։

  We hadn’t heard the new song.

  In this example, "չէինք" is used as the past perfect negative form for "լսել" (to hear).