Insert an empty line in beamer

[Ehud Behar]

I want to print the following in my beamer document:
"
First line
Second line
"

The beamer lyx doc class allows the user to insert empty line in the 
Standard layout. But even if insert more than 2 empty lines between 
"First line" and "Second line" in lyx, still there is no any empty line 
(or more correctly a \par command between them) in the generated latex 
file.

Any idea how to insert a (real) empty line in the editor?

What I do now is I insert an empty line with an ERT box.