When did Mozart music?A. started writingB. start writeC. started writeD. start writing

问题补充：

When did Mozart music?

A. started writing

B. start write

C. started write

D. start writing

答案：

A. started writing

B. start write

C. started write

(答案→)D. start writing

解析：句意：莫扎特什么时候开始创作音乐？英语中原形动词不能用作动词宾语，动名词作宾语表示抽象动作，前文已有助动词did，故行为动词用原形，选D。