A blueprint is a drawing.You use a blueprint to build a house.(改为复合句)A blueprint is a drawing ---- ---- ---- to build a house

A blueprint is a drawing.You use a blueprint to build a house.(改为复合句)A blueprint is a drawing ---- ---- ---- to build a house
A blueprint is a drawing.You use a blueprint to build a house.(改为复合句)
A blueprint is a drawing ---- ---- ---- to build a house

A blueprint is a drawing.You use a blueprint to build a house.(改为复合句)A blueprint is a drawing ---- ---- ---- to build a house
A blueprint is a drawing which---- -you--- -use--- to build a house

A buleprint that you use to build a house is a drawing.
Is this OK?

A blueprint is a drawing which can be used to help you to build a house.

A blueprint is a drawing which can be used by you to build a house.

如果是三个空的话，填 which is used