Once _,the clock will last a month and keep good time.A.start B.startedC.to start D.startingstart做启动或发动时不是用主动表被动吗?

Once _,the clock will last a month and keep good time.A.start B.startedC.to start D.startingstart做启动或发动时不是用主动表被动吗?
Once _,the clock will last a month and keep good time.
A.start B.started
C.to start D.starting
start做启动或发动时不是用主动表被动吗?

Once _,the clock will last a month and keep good time.A.start B.startedC.to start D.startingstart做启动或发动时不是用主动表被动吗?
B 省略了一些.完整的是once it is started(一旦被启动),它就……

B

B

B被动