分类：教育/科学-学习帮助
问题：宾语从句和表语语从句怎么选择连系代词？例1.Doyouknow_? 
宾语从句和表语语从句怎么选择连系代词？例1.Do you know ____  he crsed his arms?  2.That is _____ he is worried about?  请分析，谢谢。
回答：1.Do you know ____ he crossed his arms?
2.That is _____ he is worried about?
1题填why,引导宾语从句。“你知道他为什么抱着双臂吗？”
2题填what,引导表语从句。“那就是他担心的事情。”
连接词的选择取决于句中所缺的句子成分。