Learn the desk one stamp at a time. Earn up to three stars per shift — stars get you promoted.
Once you know the desk, prove it.
A rejected sentence is always turned back for one of these reasons.
Grammar fine, but it says something nobody meant — a reason where a contrast belongs.
What follows the gap doesn't fit: a clause where the linker wants a noun, or the other way round.
Correct English in the wrong clothes: report language in a text, café language in a notice.
Some answers get through with a note: they work, but a native speaker would probably have chosen differently. They count as a pass, for fewer points.
Approve a traveller with the best linker and its stamp goes in your passport. Can the class fill every page today?