—I don't know what to bring to her birthday party,        

—Why not take some flowers.  They are ____ the party.    [ ]

A. suitable for

B. suitable of

C. suit for

和自然环境打交道，就应该遵守一定的规范。人类应该首先学会遵守的规范是[ ]

①保护自然②节约资源③保护环境④远离自然

A．①②

B．②③

C．①②③

D．①②③④