在野外是in a field还是on a field

是on a field trip,还是 in a field trip 是in the field还是on the field on the field 还是in the field 意思是在田野 在单词"field"前的介词是"in"还是"on". go on a field A field 在田野里散步 应该是 go walking on the field还是 go walking in the field 在football field前面加介词on还是in! on the football field 是在足球场上 那么可不可以说 in the football field? Why can we gko on a field trip in spring Why can we go on a field trip in spring? on还是in the football field..