1 . When you finish reading this book, you will have _______ better knowledge of _______ first aid.

A．a, the

B．the, a

C．/, the

D．a, /

2 . In most western countries, on April Fool’s Day, people often play __ ___ trick on each other; children especially have great ______ fun.

A．a; a

B．the; the

C．/; a

D．a; /

3 . Wouldn’t it be ____ wonderful world if all nations lived in ____ peace with one another?

A．a; /

B．the; /

C．a; the

D．the; the

4 . Sophie dreams of walking in______ outer space like ______astronaut one day.

A．/; the

B．/; an

C．an; an

D．a; an