题干
Sun Nan got tons of ____ as soon as he announced that he would stop competing during I Am a singer.
A：joy
B：pressure
C：attention
答案(点此获取答案解析）
C
Sun Nan got tons of ____ as soon as he announced that he would stop competing during I Am a singer.
A：joy
B：pressure
C：attention
，则 
， 
互为倒数”的逆命题；②4边相等的四边形是正方形的否命题；③“梯形不是平行四边形”的逆否命题；④“若 
则 
”的逆命题，其中真命题是