中国石油服务承诺:two-out-of-three system是什么意思？

two-out-of-three system是什么意思？ 请问The winds from the southeast blow two days out of every three two to three weeks before the shipment of products two three-fers 是什么意思？ Name two or three of the most famous deserts you know in the world. How can you make 6 out of three 7's? 是什么意思 脑筋急转弯 How can you make 6 out of three 7’s? out of?? three conquest of british 李孝利的one two three four