sign your names at the students' union; sign up for it ; 都是报

sign your names at the students' union; sign up for it ; 都是报 sign up for sign up for $1 the students are supposed to come to sign up at the office o 一道完形填空求解答Students who sign up for the award will be expected sign up for trees for at the first sign sign up ,sign sign up for 等于什么? I know when it’s time to sign kids up for the pre–camp physi sign up 和 sign up for 的区别 sign up