【学习目标】To use the present perfect continuous tense correctly and properly.
【学习重难点】To learn how to use the present perfect continuous tense.
【学法指导】To compare and summarize
【知识链接】According to the text on Page38-43,complete the sentences using the present
perfect tense or the present perfect continuous tense(underline them)
1.We____________________ here for many years and-------我们在这儿进行挖掘工作多年了。
2.We _________________ human and animal bones in those caves higher up the hill as well as tools and other objects.
在高山上的那些洞穴里我们找到了人骨和兽骨，还有工具和其他物品。
3.We ___________________ fireplaces in the centre of the caves where they made fires.
我们发现在洞穴中央有生火用的地炉。
4.We ___________________ layers of ash almost six metres thick,which suggests that they might have kept the fire burning all winter.
我们一直在挖掘一层层的积灰，几乎有六米厚，这意味着他们可能整个冬天都在烤火。
We __________________any doors but we think they have hung animal skins at the cave
