In speaking activities, a speaker often tries to avoid using a difficult word or structure and chooses to use a simpler one. What learning strategy does the speaker use?

小明看书时可以“一目十行”，而小华则“一目一行”。这反映了他们在哪种注意品质上存在差异?( )   

营养素中，发热量大且食后在胃肠道停留时间最长(有饱腹性)的是( )。

学前儿童血液量与体重的比例()成人。

评价教学结果的最客观和可靠的标准是(　)。