课时作业(二十四) ⅰ.单项填空 1. if we can ________ our present difficulties， then everything should be all right. a. come across b. get over c. come over d. get off 答案 b 解析 考查动词短语辨析。句意：如果我们能克服目前的困难，一切都应该好起来的。get over有“克服；越过”的意思，为最佳选项。come across“偶然遇见”； come over“突然感到；短暂造访”； get off“下车”。 2. studies of populations ________ high levels of radiation have shown increased risk of cancer. a. exposed to b. filled in c. caught on d. kept up 答案 a 解析 考查动词短语辨析。句意：对于人们接触高核辐射
