________ pen ________ this be?　　　

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A． Who's else, can　　　 B． Who else's, can

C．Whose else, must　　　D． Whose, must

----It’s getting dark, but Mr. Johnson is still at his office.

　 ----No surprise. Who else can _____ he does?

A. do less work than B. work as hardly as

C. work as hard as D. be working hardly like

　　－I’m sorry this gold watch is not hers.

　　－What a surprise! If it is not hers, ________?

[　　]

A．Who else’s can it be

B．who else can it be

C．whose else’s can it be

D．whose can it be

—If that is not yours, ________?

—Perhaps Tom's.

[　　]

A．who else can it be

B．who's else it can be

C．whose else can it be

D．whose else's can it be

If that book is not his, ______ can it be?

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