第29题: [单项选择]已知某工程机械成孔灌注桩的总长度为1256.7m,计算实体为3568m3,扩大头部分体积为586m2,充盈量体积为850m3,则该工程桩基础工程量为( )。 A. 1256.7m3 B. 3568m3 C. 4154m3 D. 5004m3 参考答案:C
第30题: [单项选择]Returning from school, ______ . A. he found a letter in the letter-box B. a letter was found in the letter-box C. a letter was in the letter-box D. the letter-box had a letter in it 参考答案:A 答案解析:[解析] 现在分词表主动关系,从Returning这一词可看出,句子的主语应是该动作的发出者,只能是he,而不可能是a letter或the letter。