HubSpot's COS platform supports hard and soft returns. Pressing Enter or Return on your keyboard while in HubSpot's editor creates a paragraph break (a new <p> tag in the HTML). This is known as a hard return.
A soft return (Shift + Enter on your keyboard) will return your input to a new line immediately below the previous line, without breaking the paragraph or spacing. A soft return is shown as a <br> tag in the HTML instead of a new <p> tag.