I enjoy English by watching English movies.
A:to learn
B:learning
C:learn
i是虚数单位,复数5+3i4-i=( )
关于我国地理位置的叙述,不正确的是( )
躺卧看书很舒服,应当提倡(判断对错)
已知实数x,y满足2x+y-2≥0x-2y+4≥03x-y-3≤0,则x2+y2的最大值为____