I hope ______ a new sweater for my sister.
A:buy
B:to buy
C:buying
D:bought
They____ a bridge over the river a long time ago.
下列命题中:
①两条对角线互相平分且相等的四边形是正方形;
②菱形的一条对角线平分一组对角;
③顺次连结四边形各边中点所得的四边形是平行四边形;
④两条对角线互相平分的四边形是矩形;
⑤平行四边形对角线相等.
真命题的个数是( )
My brother doesn't like playing basketball __________ watching TV.
处于平静状态和剧烈运动状态下的运动员,骨骼肌细胞分解葡萄糖过程中产生的CO2摩尔数与消耗的O2摩尔数的比值分别是( )