根据语篇内容，用恰当的短语填空，使之意思完整。

     Thanks for your invitation. I'm sorry I can't visit you this week. I am    1   This evening I'm going to my cousin's house.

It's my cousin's birthday. Today I have a toothache, so I have to see the dentist tomorrow. On Friday,there will be a math

test, and I    2   On Friday evening, a new film will be on, and I'm    3   with my friends.

1. _____ 2. _____ 3._____

为促进幼苗发育和花的早日开放，应施以[ ]

A．氮肥          

B．钾肥            

C．磷肥           

D．硼肥