What is これら in japanese? Kore + ra(this + ....ra)?

Question

I've been using livemocha.com for the last two days. Doing Japanese 101. I'm lesson 3 and they use the term korera wa(ha) ki desu(これらは木です。) I think it means these but, I don't remember every hearing it before or seeing it in textbooks. Am I mistaken? I've studied Japanese for three or so years and went there as an exchange student for 6 months. I may have come across it and just not noticed but anyone know if this is correct. I didn't think they used any different words for more than one thing. That's what my books always said.

Answer 1

Ra makes it plural.

Karera= they

Korera= these

Sorera=those

Arera= those over there

Korera wa ki desu= These are trees.  

Answer 2

"ら" is used to express the plural form of pronoun.

"これら" for "these"

"あれら" for "those"

"わたしら" for "we"

"あなたら" for "you(plural)"

"かれら" for "they"

"かのじょら" for "they"

"それら" for "they"

But "たち" is used more popularly in the case of "we""you" , such as "わたしたち""あなたたち"

"たち" is also used to express the plural form of noun for person, such as "こどもたち""おとなたち"

I hope I could help you.　

Answer 3

Korera = these

Korera wa ki desu = these are trees