Today we’re speaking with Robert Hirsch, a research hydrologist for the U.S. Geological Survey, or USGS.

今天节目的嘉宾是美国地质勘探局水文专家罗伯特·赫希。

youdao

Today we’re speaking with Robert Hirsch, a research hydrologist for the U.S. Geological Survey, or USGS.

今天节目的嘉宾是美国地质勘探局水文专家罗伯特·赫希。

youdao