lock (someone or something) in:to put or keep (someone or something) in a locked place, room, etc.把…锁在(某地)
She locked her brother in the bathroom.她把她兄弟锁在了卫生间里。
They locked the jewels in a safe.他们把珠宝锁在了保险箱里。
They threatened to lock him in jail.他们威胁要把他关进监狱。
They pushed him into the room and locked him in.他们把他推进房间,锁了起来。
2
lock (something) inorlock in (something):to do something that makes you sure to get (something that could change, such as a good price, an interest rate, etc.)锁定,确定获得(某物)
If you sign the contract today, you can lock in this low interest rate before it goes any higher.如果你今天签合同,就能在利率上涨之前锁定这个低利率。