Are those banana trees?改成肯定句和否定句

Are those banana trees?改成肯定句和否定句 Are those yellow bikes old?（改成肯定句） Are those nice pictures yours?改成肯定句 Those boys are my fyiends 改成否定句 英语：把肯定句改成否定句和疑问句 把肯定句改成否定句和反问句三句. 将肯定句改为否定句：（1）There are some trees near the river 改成一般疑问句Those are his rulers.改成否定句These are apples. 肯定句改成双重否定句 双重否定句怎么改成肯定句 将下列肯定句改成否定句 Those flowers are lovely,too.怎么改为一般疑问句、否定句?肯定回答、否定回答?