at the moment

I'm in Japan at the moment.

"At the moment" means "right now" or as we are speaking.  Notice the following:

1. Can I call you back?  I'm eating dinner at the moment.
   
2. Where are you at the moment?
   

two weeks left

I've only got two weeks left here.

If you only have "two weeks left" in a place you are only going to be there for two more weeks.  Notice the following:

1. We have only five weeks left of school.
   
2. There are only two weeks left to buy concert tickets.
   

it's great

It's fun, it's great.

If something is "great" it is very good.  This is a positive adjective similar to fantastic or wonderful.  Notice the following:

1. I just finished reading a great book.
   
2. His new apartment is great!
   

pick up

Pick up a few plates.

To "pick something up" is to hold it and lift it with your hands.  Notice the following:

1. Can you pick up that suitcase and put it in the car?  It's really heavy.
   
2. She picked up her sister from the chair.
   

call

We call it the conveyor belt restaurant.

What you "call" something is the name that you have for it.  Notice the following:

1. His name is Thomas, but we call him Tubby.
   
2. We started calling this park "Paradise" after our first visit.