Mrs. Wang hasn't got any information about Peter, so she doesn't know _______ he is busy withthese days.

A.what B.how C.where D.why

My father was very angry with me _______ I broke a window.

A.although B.so that C.because D.unless

I'm sure _______ pets can make us become more responsible persons.

A.keep B.keeping C.kept D.keeps

My brother _______ as an engineer since he returned from America years ago.

A.has worked B.had worked C.was working D.will work

We should _______ people from crossing the road when the red light is on. Which of the following choices is wrong?

A.protect B.stop C.keep D.promise

The dogs in our village always bark _______ the strangers.

A.to B.at C.of D.with

These days, mum is really worried about Jenny as she _______ too much time chatting with her friends on the Internet.

A.pays B.takes C.costs D.spends

The fire _______ by the firemen in that building an hour ago.

A.is put out B.was put out C.put out D.puts out

Keeping dogs in small spaces may make them _______ extremely sad.

A.feels B.to feel C.feel D.feeling

_______ important work the teachers are doing! Let's show our respect for them.

A.What B.What a C.What an D.How