.All work is pleasant_ ______when the habit of working is fo

.All work is pleasant_ ______when the habit of working is formed. A. done B. doing C. to do
.All work is pleasant_ ______when the habit of working is formed.
A. done B. doing C. to do D. to be done
C
不定式的主动表被动的一种情况.
“主语+be+形容词+to do”中,当主语是不定式的逻辑宾语时,要用主动表被动,相当于省略了逻辑主语for us,for you等.
——————————————————————————————
此解释中“主语+be+形容词+to do” 是固定句型还是
在pleasant后要跟to do? 除了work to do 还有什么可以主动表被动的?

就是你前面的那个解释!
此句的主语是后面不定式的逻辑宾语
其句型是：
【主语+is(was)+ 形容词+ to 动词原形】
如：
The question is easy to answer.
The maths problem is difficult to work out.
He is easy to get along with.