Why did he get up early this morning? _____________

问题描述:

Why did he get up early this morning? _____________
1 Catch the early bus2 Caught the early bus 3 To catch the early bus 4 Catches the early bus

答案:3
动词不定式结构在句中作目的状语.
翻译:
--今天早上你为什么起得这么早?
--为了赶上早班车.