She had great difficulty ________ the suitable food on the menu in that restaurant.
A:finding
B:find
C:found
D:to find
心中有规则,社会才能从无序走向有序。只有增强自立精神,做到心中有规则,我们的心灵才能获得真正的自由。下列选项属于缺乏自律的行为的是( )
观察下列各式:a+b=1,a2+b2=3,a3+b3=4,a4+b4=7,a5+b5=11,…,则a10+b10=( )