Be sure to hand in your English homework by tomorrow morning 中 为什么要用by这个介词呢? 速度~~速度速度~~不是要问意思 是要解释 为什么要用by啊

believe in yourself be sure to Be sure to ___ your names before you hand in your papers.A.write down B.look up C.turn down D.send up 这句话怎么理解合适On the other hand,I want you to know that the material will be purchased in China as I will be producing in China itself.I’m not sure if this will change things. It is important for them to be in a hand. be sure of 和 be sure to be sure to do We will go to the end hand in hand,and be happy everyday! We will go to the end hand in hand,and be happy everyday! sure thing,to meet with you in Washington,we will be there from 16~18sure 用Be sure to、Be sure to do 、Be sure of、Be sure that 造句 Be sure to hand in your English homework by tomorrow morning 中 为什么要用by这个介词呢? 速度~~速度速度~~不是要问意思 是要解释 为什么要用by啊 at hand,by hand,in hand,on hand,to hand ,with hand Hand-in-hand to death do us please make sure that you have got a c_____ answer befor you hand in your paper to me be sure to do sth. be sure to go there they are sure to be make sure,be sure of ,be sure to do,for sure的区别