Breakdown of Det ligger en tom bricka på bordet.
en
a, an (common)
bordet
the table
på
on / at / for (wait for) / in (believe in)
tom
empty
Questions & Answers about Det ligger en tom bricka på bordet.
Why do we say Det ligger instead of Det är to mean "There is"?
In English, you say "There is a tray", but Swedish prefers to describe exactly how the object is positioned. Because a tray (en bricka) is flat and placed horizontally on the table, we use ligger (lies). If it were an upright object like a bottle, we would use står (stands) instead.
Could I just say En tom bricka ligger på bordet without using Det?
Yes, that is grammatically correct and means "An empty tray is lying on the table." However, when introducing a new, undefined object into a known location, Swedish strongly prefers starting with the presentational Det (literally "It"), exactly like how English uses "There is...".
Why is the adjective tom and not tomt?
The adjective has to match the noun it describes. Since en bricka is an en-word in the singular, the adjective takes the basic form tom. If we were talking about an ett-word, like ett glas (a glass), it would change to ett tomt glas.
Why is bordet in the definite form (the table) while the tray is indefinite (en tom bricka)?