第27题: [单项选择]蜜蜂美洲幼虫腐臭病具有诊断意义的症状是 A. 房盖有穿孔 B.烂虫能拉丝 C.房盖颜色加深 D.房盖出现下陷 B. 烂虫有腥臭味 参考答案:B
第28题: [单项选择]______ the 1990's that the trade between the two countries reached its highest point. A. During B. It was in C. That it was in D. It was 参考答案:B 答案解析:[解析] 本题考查强调句型。强调句的句型为“It is/was+被强调部分+that/who+其他成分”。如果强调的是人,应用who,其他情况均使用that。本题去掉相关部分It was和that后仍