shift-return for new line?

I need help please with a simple thing. (I tried various searches here and with the manual and on Google, but the terms are too generic to show results.)

In some places in a document in Scrinever, I don’t need a new paragraph (via Return), but I need a new line, right under the existing line. In every word processor I’ve used so far, Shift-Return does that. But not with Scrivener.

Ideas please?

Opt-Cmd-Return. (Edit > Insert > Line Break)

thank you very much!