They have some problems ____ for the party.A, prepare B, to prepare C, prepared D, preparing答案是D,怎么解释?

They have some thing in________. They have some books(改为一般疑问句) some,they,have,juice连词成句 they have some sweets.一般疑问句 they have some ruler变一般疑问句 They have got some toys.一般疑问句 they have some beans.(改为否定句) They have some English stamps改单数 have they got some postcard?英语回答 They have some toys.改为否定句 they have some ( )at the party.(candy) What____The childred__?They have some fruit F_____ lunch they have some sandwiches. They have some knives.改为单数 They have some pots(改为单数） they have just had some sandwiches . They have some oranges(改为单数形式) They have some gloves.改为一般疑问句