填介词+关系代词 He built a telescope ,_______ he could study the sky 翻译并说明理由

He built a telescope ,_by which he could study the sky
先行词在从句中做方式状语
he could study the sky 【by the telescope】
所以用by which可是老师说用 throughwhich应该是三个介词都可以的He built a telescope , 【by/with/through which】 he could study the sky