根据句意和汉语注释，在答题卡标有题号的横线上，写出单词的正确形式。
I’m afraid we can’t order this kind of machine. It is slow and heavy by modern ________ (标准).
My mother is always ________ (鼓励) my father in his choice of career.
The meat was so tough that I ________ (简直) couldn’t get it down.
You won’t get paid for time off ________ (除非) you have a doctor’s note.