The cave might never have been discovered had not the entrance been spotted by the distinguished French potholer, Berger. (NCE 3, L.42)在无连词条件从句中,not必须放在主语之后,而且不能使用-n't这种缩略形式。因此,上句是否应该改成...had the entrance...
Anyone who commutes by car knows that traffic jams are an inevitable
part of life. 句子出处,http://www.kekenet.com/broadcast/202009/617806.shtml traffic jams are an 为什么谓语动词是复数are,后面用an?traffic jams are an....part 为什么jams复数,后面用冠词an?
Economy news can appear in every section. Most international news has a crucial economic aspect to it. 这句主要是讲杂志的版面涉及经济新闻。请教老师,it指代的是前句的every section 吗?to 是对于,至于的意思?该如何理解?