题干
That was the first time I _______ there and I was impressed by the friendly people very much
A：go
B：was going
C：had gone
D：have gone
答案(点此获取答案解析）
C
A：go
B：was going
C：had gone
D：have gone
名称是1，3﹣二甲基﹣2﹣丁烯