It is really a challenge for me to finish it．In order not to be disturbed, I spent three days ________ in my study surfing the internet to do the research．
A.locking
B.locked
C.to lock
D.lock
网友回答
B解析本题A项干扰性较强，有的学生受思维定势的影响，看到locking，就不假思索地选A项。解本题时，应仔细分析其语境和结构，细心揣摩句意。sb．spend time(in)doing中的sb．是doing的逻辑主语。如：He spent three years writing the book．＝He wrote the book in three years' time．从结构和句意看，本题中的主语I和lock不是主动关系，而是被动关系，故选B项。如果在in之前加反身代词myself，本题就选A项。