常用in、on、at作介词开头的词组答:at a bookshop, at a distance(在远处), at that place, at the airport, at the back of, at the base of, at the bottom of, at the centre (of)(在中心), at the corner, at the crossroads, at the desk(在书桌旁), at the door, at the edge of, at the end of, at ...