Easy for an ABC to say.

My son is finishing his third year of Mandarin and he's getting quite good at reading and writing. However even though he has a great "ear" he struggles with oral comprehension.

The tones can be very difficult for Westerners. He can make his way through one-on-one conversations with a little back and forth to confirm his understanding. But he says listening to a native speaker at full-speed everyday conversational rate drives him crazy. For his oral comprehension tests, the teacher often reads a moderately-long passage and then the students have to write two or three paragraphs responding to what was read. This is the part of the test where he gets his lowest grades.