28. They ____ friends since they met in Shanghai ten years ago.

A teacher may also make a mistake if he or she is not _______.

Look, John‘s fallen asleep at work!—Oh, he must have ________ late last night.

Lu Jialei, the winner of the CCTV Chinese Character(汉字) Spelling Contest, said, “I am not the smartest one, but I ______ details. “

Ane got an “A” in the Maths test.— . She works the hardest in our class.