1. ~ down:
put down放下 shut down把…关上cut down砍掉 come down下来、落下slow down 减缓、放慢 sit down坐下write down写下 get down下来,降落
2. after ~:
after all毕竟.终究 after that于是.然后day after day日复一日地one after another相继.挨次soon after不久以后the day after tomorrow后天name after根据……命名run after追赶
3. ~ up (with):
come up with找到、提出、赶上
catch/keep up with赶上
