to fix a large piece of equipment or system into a room or building, ready to be used

I've just had central heating/a new kitchen put in. 我刚刚安装了一个中央供暖系统／一个新厨房。

to formally offer a particular thing to be considered

I've put in an application to the college. 我已经向这所大学提交了报名申请。

They've put in a bid for the company/a bid to buy the company. 他们投标购买该公司。

to say something that adds to or interrupts what is already being said

[ + speech ] "But she's too inexperienced for the job," put in Jane. “但是这份工作她很缺乏经验，”简插嘴说。