帮我分析这两个句子的语法结构

题目

帮我分析这两个句子的语法结构
主要是谓语那一块：
1.Surely we should be having fewer babies in order to reduce Earth's population ,not cloning more.这一句中的should be having
2.After all,scientist have been challenging quertions of morality for centuries.这一句中的have been challenging

答案

1.这里的简单句是we should be having fewer babies,should not be cloning more.这里should是情态动词,应该.用be doing来表示将来含义.我们应该要少一点的孩子,而不是越来越多.2.用have been doing来表示某件事情从...