【单选题】关于胎儿发育下列哪项正确
A.
妊娠4周末,B型超声可见早期心脏形成并有搏动
【单选题】2 It ’ s high time we ____ something to stop air pollution.
【单选题】I think it ’ s high time we__________measure to protect the environment.
【单选题】—Just a moment. I haven" finished packing my suitcase.— . It,s high time we left for the airport.