If you cannot see, you may not be able to1 find your way out of a burning building and that could be fatal. A company in Leeds could change all that2____1____ directional sound alarms capable of guiding you to the exit.
Sound Alert, a company____2____ the University of Leeds, is installing the alarms in a residential home for____3____ people in Sommerset and a resource centre for the blind in Cumbria.____4____ produce a wide range of frequencies that enable the brain to determine where the____5____ is coining from.
Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be____6____ by humans. It is a burst of white noise____7____ people say sounds like static on the radio， she says. Its life-saving potential is great.
She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of3 a large____8____ room. It____9____ them nearly four minutes to find the door____10____ a sound alarm, but only 15 seconds with one.
Withington studies how the brain____11____ sounds at the university. She says that the____12____ of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms____13____ the same concept have already been installed on emergency vehicles.
The alarms will also include rising or falling frequencies to indicate whether people should go up____14____ down stairs. They were____15____ with the aid of a large grant from British Nuclear Fuels.
词汇：
directional / d?rek??nl; da?- / adj.定向的
exit / eks?t / n.出口
install / ?nst?:l / v.安装
residential / rez?den??l / adj.居住的
static / st?t?k / n.静电噪声
potential / p?ten??l / n.潜力
thermal-imaging热效应成像
pinpoint / p?np??nt / v.精确地确定
concept / k?nsept / n.概念，观念
emergency / ?m??d??ns? / n.紧急情况
grant / grɑ?nt / n.授予物，准许
注释：
1.在谓语动词中，不能并列使用两个情态动词，如may和can就不能并列使用。如果由于表达需要，要同时用可能和能够，就得说成may be able to。如：
I may be able to come tomorrow, but I cannot promise.
我可能明天来，但我不可能作出承诺。
2.that指第一句所表达的意思。
3.... find their way out of ...：意为找到从出去的路。
练习：
1.A without B with C having D selling
2.A run by B changed by C decorated by D criticized by
3.A slow B deaf C blind D lame
4.A Alarms B Alarm C The alarm D The alarms
5.A noise B sound C music D bell
6.A watched B produced C learnt D heard
7.A where B what C that D how
8.A smoked B smoke-filled C filled with smoke D smoke-filling
9.A has taken B takes C took D will take
10.A on B near C without D from
11.A processes B produces C possesses D proceeds
12.A feature B quality C diagram D source
13.A basis on B base on C basing on D based on
14.A or B and C but D otherwise
15.A developed B determined C discovered D delivered