已知函数$f\left(x\right)=(x+1)(2x+1)(3x+1)\cdots (nx+1)$，则$f^{\text{'}}\left(0\right)=$(    )

    We have a big playground in our school .We all like to 1 games 2 after school .It's Friday .We have only two classes 3 the afternoon . 4 school is over（结束的）,a lot of students go to the playground quickly.  The boys of Grade Two often 5 soccer. The girls like 6 them playing .Soccer is their favorite sport . Their teacher Mr Li also 7 football. Li Ming , Li Lei and Wei Fang are students of Grade One .They sometimes play 8 the students of Class Two. It’s half past five 9 . It's time 10dinner . My father is waiting for me at the school gate .

《爱莲说》中点明了全文主旨的句子是____，____。