In order not to be disturbed I spend three days in my study.A. lockingB. lockedC. to lo

问题补充：

In order not to be disturbed, I spend three days in my study.

A. locking

B. locked

C. to lock

D. lock

答案：

A. locking

(答案→)B. locked

C. to lock

D. lock

解析：这题很容易受句型spend time in doing sth.的影响而选A，但这里要表达的意思是：把自己关在书房里，所以用过去分词，表示被动。