A balloon______it.(pin/a/if/stick/you/bursts/into/it)这是关于一个条件状语从句
问题描述：
A balloon______it.(pin/a/if/stick/you/bursts/into/it)
这是关于一个条件状语从句
答
A ballon bursts if you pin a stick into it.
答
A ballon bursts if you stick a pin into it