Information technology is taught in most schools，________ we have entered the information era.

A．so B．while

C．for D．still

________ several times，but he still doesn't know how to do it correctly.

A．Although I've taught him

B．I've taught him

C．Having been taught

D．Having taught

(2013·北京，21)Volunteering gives you a chance ________ lives, including your own.

A．change B．changing C．changed D．to change

(2013·福建，22)________ basic first－aid techniques will help you respond quickly to emergencies.

A．Known B．Having known

C．Knowing D．Being known

(2013·山东，33)________at the cafeteria before，Tina didn't want to eat there again.

A．Having eaten B．To eat

C．Eat D．Eating

(2013·湖南，25)The sun began to rise in the sky，________the mountain in golden light.

A．bathed B．bathing

C．to have bathed D．have bathed

(2013·湖南，31)________warm at night, I would fill the woodstove, then set my alarm clock for midnight so I could refill it.

A．Staying B．Stayed C．To stay D．Stay

(2013·江苏，31)Shortly after suffering from a massive earthquake and________to ruins，the city took on a new look.

A．reducing B．reduced

C．being reduced D．having reduced

(2013·辽宁，28)Laura was away in Paris for over a week.When she got home，there was a pile of mail________for her.

A．waited B．to wait C．waiting D．was waiting

(2013·陕西，13)Let those in need ________ that we will go all out to help them.

A．to understand B．understand

C．understanding D．understood