At a hastily arranged press conference at the White House after news of the switch leaked overnight, Obama said the aim was to protect against the threat of an Iranian missile attack.

转变的消息很快被泄露出去，在白宫匆忙安排的新闻发布会上，奥巴马表示此举目的是防止伊朗导弹攻击的威胁。

youdao

Just imagine if changing the light in your room requires you to change the switch also. Would you care to purchase and set up such a system in your house?

想想一下，如果改一下房间里的灯同时需要改开关，你会乐意在你房子上花钱并安装这个系统吗？

youdao

IMAGINE redecorating your house at the flick of a switch, or changing the colour of your coat at the press of a button.

可以想象一下通过旋动按钮可以重新装修房子，或者是通过按钮可以改变衣服的颜色。

youdao

Lighthouse authority Trinity House plans to switch off Godrevy light on the edge of St Ives Bay by 2010.

BBC: NEWS | UK | England | Cornwall | Lighthouse switch-off considered

"The attorney general has been asleep at the switch while the White House runs the Justice Department, " he said.

CNN: By Dana Bash/

How -- substantively, how significant is this switch to the White House?

WHITEHOUSE: Press Briefing