Simple problem?

In actionscript 2.0 I used to refer to movieclips in arrays like this:

[COLOR=Red][“movieclip” + z][/COLOR]._x = thumbArrayX[z];

The bit in red is the problem. When I run the movie, actionscript 3 doesn’t like the syntax. I just need a way of grouping a string with a variable I think… :pa:

Much obliged if anyone could help me out.