"There is less time than I thought."
Translation:Hay menos tiempo de lo que yo pensaba.
A more literal translation would be: "there is less time than what I thought."
The "de" in the sentence is often used in comparisons in the same way that "que" is used, but mainly in certain contexts, such as when numbers are involved.
Remember, "lo que" means "that which" or more loosely, "what"
That's not quite what Duo is asking to translate, though. "Queda" is "remains," implying that time has passed. "There is less time" does not necessarily mean that any time has passed.
I got the de lo que - no problem there. Someone please explain why del would be needed? I get the de part, but EL? El what?
del would be a combination of de + el with el referring to time. the "el" is needed to avoid confusion with the structure "de que", which means "that" in the sense of a conjunction. A more literal translation would than be: there is less time of it than I thought. it referring to the time. it sounds quite stupid in english but it is just the way it is done in spanish. point I.3 in this link also explains this http://users.ipfw.edu/jehle/COURSES/relpron1.htm