1 Some site design their agents to tempt job hunters to reyurn.
to tempt job hunters to reyurn是不是不定式做宾补?
是的!
2 Some use them to keep a close watch on the demand for their line of work or gather information on compensation to arm themselves when negotiating for a raise.
to keep a close watch on the demand for their line of work是不是宾补?
是目的状语!
3 People search agents are also helpful to those already employed.
to those already employed.是不是宾补?
是介词短语,与‘helpful to ...’是词组!
4 It is not simply to raise everyone's job prospects that all children are legally required to attend school into their teens.主,谓语,宾语?
It （形式主语）is not simply to raise everyone's job prospects that （that 引出实际主语）all children are legally required to attend school into their teens.
5 There are some good arguments for a technical education given the right kinf of student.
given the right kinf of student.是technical education的定语吗?
是的!