John Smith, a diligent student, never refuses to （ ） more responsibilities that are assigned to him.

I cannot tell the_____difference between the twins.

The color of the skirt does not （ ） that of the coat.

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

I won’t call you, （ ） something unexpected happens.

He studies so hard to avoid （ ） at the bottom of the class.

You needn’t introduce him to me. I’ve met him on several _____.

By the end of this term, we （ ） 3000 English words in all.

Only those who have tasted bitterness will （ ） among others.

A car （ ） Jane’s cat and sped away.

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

（ ） when she started complaining.