In the dark street, there wasn’t a single person _____ she could ask for help. [ ]

We have sweaters____all colors_____ 50 each.[ ]

How careless Tom is! He forgot to remind his boss _____ the important meeting yesterday. 一 What is terrible! I am afraid his boss will never forgive him _____ his carelessness. [ ]

“ ________ does Kitty dance?” “Three times a day.”

It was very late, but the teachers were ________ working hard in the office.