杏的果实中可食用的部分是由杏花中的哪个部分发育来的( )
下列说法不正确的是( )
已知等差数列{an}前四项中第二项为606,前四项和Sn为3834,则该数列第4项为( )
The little pupil took his grandma ____ the arm and walked her across the street.