18.（ ）

(单选题)Looking at the ratings on Amazon products can help consumers (单选题)Most importantly, reading is my favorite thing to do because (单选题)The change to some higher color in a leaf is an ______ that (单选题)Julie, my new roommate, claimed to be 18 years old, ______ I (单选题)Over the last few years, a wave of faux-barns, designed ____ (单选题)High speed trains are a type of passenger train travel that  (单选题)15.（ ） (单选题)14.（ ） (单选题)13.（ ） (单选题)12.（ ）