【题目】In the past six years, Nadia Lalak environment-centered stories for school children.
A. has been writing B. is writing
C. will be writing D. have writ ten
在线课程【答案】A
【解析】考查时态。句意：在最近的六年里，Nadia Lalak k一直在为学校的孩子们撰写以环境为中心的故事。根据In the past six years可知句子用现在完成时态，因为此处强调进行，故用现在完成进行时态，故选A。