I___________ frustrated when I wasn’t sure of the correct answer.
–Can you go shopping with me tomorrow? --_____. But I have a lot of work to do.
My mother is busy_____ the room.
The harder we work, the_____ result we will get.
–The classroom is_____ clean_____ it was yesterday. --Sorry, I forgot to clean it.
Every day the boss makes him_____ 12 hours.