English (obviously, though many Americans ask me what my "third" language is after I state the other two. I have to remind them that I am speaking that third language!)
French (I spent 4 years in Geneva, Switzerland from 1975 to 1979, where I worked for Swissair. I had to relearn English when I returned).
Spanish (I also spent 4 years in Apizaco, Tlaxcala, Mexico, from 1980 to 1984. I had to relearn English when I came back as well).
When I say I had to relearn English, I don't mean that I lost all knowledge of the language. I just didn't use it for four years and both times, when I returned to the US, I found it difficult to carry on a conversation in English.
A supply chain manager controls the inventory, or stock, of a company from the creation of a purchase order to buy raw materials, to the shippment of a finished product to a customer. He also controls all production throughput, stock levels, overages, obsolete material, bad material, backorders, late deliveries, and anything else that has to do with materials.