Police warned bystanders to keep __________ the blazing building.

The police warned people to be ______ against burglary during the festival.

A．in guard

B．on guard

C．under guard

D．like guard

A.worn

B.wore

C.warm

D.warned

A.approach

B.beyond

C.replace

D.enroll

A.guard

B.attack

C.duty

D.safe

A.at guard

B.on ears

C.guard our attention

D.on guard

A.was warned,would not eat

B.had been warned,would not have eaten

C.would be warned,had not eaten

D.would have been warned,had not eaten

一If he________，he __________that food.

一Luckily he was sent to the hospital immediately.

A. was warned;would not take

B. had been warned;would not have taken

C. would be warned; had not taken

D. would have been warned; had not taken

A．has been warned

B．have been warned

C．has warned

D．have warned

A.warns

B.warned

C.is warned

D.was warned

A.A.

B.B.warned

C.C.have warned

D.D.have been warned

E.E.were warning