I cannot tell the_____difference between the twins.

I can’t find my keys! Can you help me （ ） them?

The kidney transplant operation was _____ complicated， so the operating team had to take special care to ensure its success.

I love thinking of new designs. It keeps my mind clear and active and fills my retired life with （ ）.

It is very expensive to （ ） the fashion.

Thank you for your letter of May 6, in which you _____ about the bicycles of Model 897.

（ ） when she started complaining.

Only when （ ） in the afternoon （ ） able to leave.

Patients’bills of rights require that they （ ） informed about their condition and about alternatives for treatment.

It’s vital that enough money_____collected to get the project started.

The two boys had so _____ in common that they soon became good friends.

Mary likes classical music _____ her brother likes pop music.