【题目】Because he _____himself to _____his research, he spared no time to spend to weekend with us.
A.was devoted; doing
B.devoted; do
C.was devoted; do
D.devoted; doing

【答案】D
【解析】句意：因为他献身于他的研究，所以他不惜一切地和我们一起过周末。devote oneself to doing sth./be devoted to doing sth.固定短语，“献身于做某事”，根据句意可知答案为D。