1．____________(似乎没必要) for you to go there on your own.(there be)
2．____________(乍一看), the difficulty looks greater than it really is.(sight)
3．Our headmaster likes to arrive at school early, ______________(为其他老师树立了榜样)．(example)
4．It is impossible ____________(满足每个人的需求)．(demand)
