问题补充:
have has 句子中的意思,In recent years the focus has intensified as scientists have learned more about its importance.并翻译之.
答案:
这个句子没有提供上文内容,无法所指的特定事物,只能将句子按字面意思翻译如下:In recent years the focus has intensified as scientists have learned more about its importance.近年来,当科学家们已经更了解到关...