<em>- </em><em>Ellos </em><em><u>estaban esperando</u></em><em> en la fila.</em>
Explanation:
The translation of the sentence is:
- They <u>were waiting</u> in line.
The time that mentions the actions that are carried out at a certain moment is the progressive time or continuous time, which is characterized by two things:
1. The use of the verb <em>"estar"</em> in the respectively tense:
Reduce the number of trips you take in your car. Reduce or eliminate fireplace and wood stove use. Avoid burning leaves, trash, and other materials. Avoid using gas-powered lawn and garden equipment.