试题题干
（ ） exploration during the 1960s and early 1970s led to the discovery of a large deposit of zinc ore at Navan in northeast Ireland.
参考答案
正确答案：
试题解析
20世纪60年代和70年代初期的矿产勘查导致了在爱尔兰东北部纳文发现了大量的锌矿石。
（ ） exploration during the 1960s and early 1970s led to the discovery of a large deposit of zinc ore at Navan in northeast Ireland.
20世纪60年代和70年代初期的矿产勘查导致了在爱尔兰东北部纳文发现了大量的锌矿石。