they should walk in time to the music这句话中的in time 如何理解

they should walk in time to the music这句话中的in time 如何理解 They should walk and l____ to the music Passengers should allow for___travel time to the airport in they failed to finish the project in time.i regretted______t 这句话中的lead in 都是什么词性?spend some time leading in to a question put in the time to they _____(success) in finishing the work on time at last这句话 （In fact,they continue to usual time. they should spend their time on schoolwork in order to get g In Russia people should when they meet for the first time She try to best to finished the task in time.这句话有语法错误吗? Are you often listen to music in your free time?