Read and judge. (读下面的短文并判断“T”或“F”)    

     I went to Hainan with my parents this Spring Festival. On Monday , I went swimming in the sea.

The next day, I went to Wuyi Mountain. It's beautiful. We went to Sanya on Wednesday. There is

a beautiful bay (湾). We ate seafood there. The last day, we went to Ultima Thule (天涯海角).

We took many pictures there. We got back home by plane on Friday. We had a good time.    

( )1. Our family went to Hainan this Spring Festival.    

(     )2. I went to swim in the swimming pool.    

(     )3. The second day , we went to Wuyi Mountain.    

(     )4. We took many pictures in Sanya.    

(     )5. We went home by train.

以下有关酶偶联法测定酶活性浓度的描述，错误的是

A．往往利用一个以上的工具酶

B．测定延滞期越短越好

C．指示酶的反应必须是一级反应

D．一般指示酶的Km值都很大

E．指示酶的用量要适量