21.（ ）

(单选题)Chondrites are stony meteorites ______ modified due to melti (单选题)______ which way to take, the little boy behaved like a real (单选题)Ms. Nancy didn’t mind at all ______ to the ceremony. (单选题)______ evidence that language acquiring ability must be stim (单选题)Tomorrow the mayor is to ______ a group of Canadian business (单选题)Mrs. Morris’s daughter is pretty and ______, and many girls (单选题)These teachers try to be objective when they ______ the inte (单选题)As he has ______ our patience, we’ll not wait for him any lo (单选题)The machine looked like a large, ______, old-fashioned type (单选题)This robot is supposed to save a lot of labor, but it remain