I saw this paragraph in a TOEIC sample test.
My brother-in-law tried his best to assemble the seat as he saw from the diagrams in the instructions and from his best judement though it to be safe. However, the belt buckle mechanism was very easy for my niece to open by herself, and did so on a car journey.
My question: is "though" a conjunction?
Is this phrase "though it to be safe" grammatically correct?