Hi!
Answer:
→ PLURAL
1. Las luces
2. Los bistecs
3. Unas cruces
4. Unos peces
5. Los blocks
6. Unos bistecs
→ The plural expresses more than one unit of beings or objects to which the word in which it is manifested refers or applies
They end in a consonant, in addition to the "s", they add an "e" to facilitate pronunciation. For example: papeles, relojes
SpanishGirl, Greetings!