A. It comes from rain.
B. It comes from river.
C. It comes from vapour.

(     ) 1. A. Where does the rain come from?    
            B. Where does the cloud come from?     
(     ) 2. A. It comes from the clouds.    
            B. It comes from the vapour.     
(     ) 3. A. How can the water become vapour?    
            B. How do you do that?    
(     ) 4. A. —What should you do then?    
                 —Water it.    
             B. —What should you do then?  
                 —Put it in the sun.        
(     ) 5. A. —Where are you going?             
                 —I'm going to the sky.          
             B. —Where are you going?             
                 —I'm going to school.

1. A: W___________ does the rain come from?
    B: It comes f___________ the clouds.
2. A: Where does the cloud c___________ from?
    B: It comes from the v___________.
3. A: W___________ are you going to do tomorrow?
    B: I'm going to p___________ a flower. 
    A: H___________ do you do that? 
    B: First, put a flower seed in the s___________.
    A: What should you do t___________? 
    B: W___________ it. Put it u___________ the sun every day. Then you c___________ see 
        a flower s___________.