Expertshavefoundthatnormalsleepcanbedividedintofive______stages
电子以平行于磁场方向的初速进入均匀磁场，忽略重力作用，该电子做（）
Whentheshiplostitsenginepower,thecrewfoundthemselvesatthe_________ofthewind.
Ithoughtherrequestforfinancialaidwas___(reason),butsomehowitwasrefused.
Don’tworry.Thisisthe________(desire)weightrangeforyouhealth
