原题
录音 1
What does the speaker say about the sluice gates used in ancient Hawaiian fishponds?
AThey were destroyed after the fish in the ponds were harvested.
BThey could open and close automatically with incoming and outgoing tides.
CThey allowed young fish to enter the ponds and kept older fish inside them.
DThey prevented agricultural runoff from nearby fields from entering the ponds.
正确答案：C
解题思路
老师暂未填写解题思路。